[vbus] Use stack-based hex formatting in verbose logging

2025.12.4

.clang-tidy.hash

@@ -1 +1 @@
-4268ab0b5150f79ab1c317e8f3834c8bb0b4c8122da4f6b1fd67c49d0f2098c9
+94557f94be073390342833aff12ef8676a8b597db5fa770a5a1232e9425cb48f

MANIFEST.in

@@ -1,6 +1,7 @@
 include LICENSE
 include README.md
 include requirements.txt
+recursive-include esphome *.yaml
 recursive-include esphome *.cpp *.h *.tcc *.c
 recursive-include esphome *.py.script
 recursive-include esphome LICENSE.txt

docker/Dockerfile

@@ -11,6 +11,16 @@ FROM base-source-${BUILD_TYPE} AS base
 
 RUN git config --system --add safe.directory "*"
 
+# Install build tools for Python packages that require compilation
+# (e.g., ruamel.yaml.clibz used by ESP-IDF's idf-component-manager)
+RUN if command -v apk > /dev/null; then \
+        apk add --no-cache build-base; \
+    else \
+        apt-get update \
+        && apt-get install -y --no-install-recommends build-essential \
+        && rm -rf /var/lib/apt/lists/*; \
+    fi
+
 ENV PIP_DISABLE_PIP_VERSION_CHECK=1
 
 RUN pip install --no-cache-dir -U pip uv==0.6.14

esphome/__main__.py

@@ -431,25 +431,33 @@ def run_miniterm(config: ConfigType, port: str, args) -> int:
     while tries < 5:
         try:
             with ser:
+                buffer = b""
+                ser.timeout = 0.1  # 100ms timeout for non-blocking reads
                 while True:
                     try:
-                        raw = ser.readline()
+                        # Read all available data and timestamp it
+                        chunk = ser.read(ser.in_waiting or 1)
+                        if not chunk:
+                            continue
+                        time_ = datetime.now()
+                        nanoseconds = time_.microsecond // 1000
+                        time_str = f"[{time_.hour:02}:{time_.minute:02}:{time_.second:02}.{nanoseconds:03}]"
+
+                        # Add to buffer and process complete lines
+                        buffer += chunk
+                        while b"\n" in buffer:
+                            raw_line, buffer = buffer.split(b"\n", 1)
+                            line = raw_line.replace(b"\r", b"").decode(
+                                "utf8", "backslashreplace"
+                            )
+                            safe_print(parser.parse_line(line, time_str))
+
+                            backtrace_state = platformio_api.process_stacktrace(
+                                config, line, backtrace_state=backtrace_state
+                            )
                     except serial.SerialException:
                         _LOGGER.error("Serial port closed!")
                         return 0
-                    line = (
-                        raw.replace(b"\r", b"")
-                        .replace(b"\n", b"")
-                        .decode("utf8", "backslashreplace")
-                    )
-                    time_ = datetime.now()
-                    nanoseconds = time_.microsecond // 1000
-                    time_str = f"[{time_.hour:02}:{time_.minute:02}:{time_.second:02}.{nanoseconds:03}]"
-                    safe_print(parser.parse_line(line, time_str))
-
-                    backtrace_state = platformio_api.process_stacktrace(
-                        config, line, backtrace_state=backtrace_state
-                    )
         except serial.SerialException:
             tries += 1
             time.sleep(1)
@@ -796,7 +804,13 @@ def command_compile(args: ArgsProtocol, config: ConfigType) -> int | None:
     exit_code = compile_program(args, config)
     if exit_code != 0:
         return exit_code
-    _LOGGER.info("Successfully compiled program.")
+    if CORE.is_host:
+        from esphome.platformio_api import get_idedata
+
+        program_path = str(get_idedata(config).firmware_elf_path)
+        _LOGGER.info("Successfully compiled program to path '%s'", program_path)
+    else:
+        _LOGGER.info("Successfully compiled program.")
     return 0
 
 
@@ -846,10 +860,8 @@ def command_run(args: ArgsProtocol, config: ConfigType) -> int | None:
     if CORE.is_host:
         from esphome.platformio_api import get_idedata
 
-        idedata = get_idedata(config)
-        if idedata is None:
-            return 1
-        program_path = idedata.raw["prog_path"]
+        program_path = str(get_idedata(config).firmware_elf_path)
+        _LOGGER.info("Running program from path '%s'", program_path)
         return run_external_process(program_path)
 
     # Get devices, resolving special identifiers like OTA

esphome/components/a01nyub/a01nyub.cpp

@@ -30,7 +30,9 @@ void A01nyubComponent::check_buffer_() {
       ESP_LOGV(TAG, "Distance from sensor: %f mm, %f m", distance, meters);
       this->publish_state(meters);
     } else {
-      ESP_LOGW(TAG, "Invalid data read from sensor: %s", format_hex_pretty(this->buffer_).c_str());
+      char hex_buf[format_hex_pretty_size(4)];
+      ESP_LOGW(TAG, "Invalid data read from sensor: %s",
+               format_hex_pretty_to(hex_buf, this->buffer_.data(), this->buffer_.size()));
     }
   } else {
     ESP_LOGW(TAG, "checksum failed: %02x != %02x", checksum, this->buffer_[3]);

esphome/components/a02yyuw/a02yyuw.cpp

@@ -29,7 +29,9 @@ void A02yyuwComponent::check_buffer_() {
       ESP_LOGV(TAG, "Distance from sensor: %f mm", distance);
       this->publish_state(distance);
     } else {
-      ESP_LOGW(TAG, "Invalid data read from sensor: %s", format_hex_pretty(this->buffer_).c_str());
+      char hex_buf[format_hex_pretty_size(4)];
+      ESP_LOGW(TAG, "Invalid data read from sensor: %s",
+               format_hex_pretty_to(hex_buf, this->buffer_.data(), this->buffer_.size()));
     }
   } else {
     ESP_LOGW(TAG, "checksum failed: %02x != %02x", checksum, this->buffer_[3]);

esphome/components/addressable_light/addressable_light_display.h

@@ -25,11 +25,13 @@ class AddressableLightDisplay : public display::DisplayBuffer {
       if (enabled_ && !enabled) {  // enabled -> disabled
         // - Tell the parent light to refresh, effectively wiping the display. Also
         //   restores the previous effect (if any).
-        light_state_->make_call().set_effect(this->last_effect_).perform();
+        if (this->last_effect_index_.has_value()) {
+          light_state_->make_call().set_effect(*this->last_effect_index_).perform();
+        }
 
       } else if (!enabled_ && enabled) {  // disabled -> enabled
-        // - Save the current effect.
-        this->last_effect_ = light_state_->get_effect_name();
+        // - Save the current effect index.
+        this->last_effect_index_ = light_state_->get_current_effect_index();
         // - Disable any current effect.
         light_state_->make_call().set_effect(0).perform();
       }
@@ -56,7 +58,7 @@ class AddressableLightDisplay : public display::DisplayBuffer {
   int32_t width_;
   int32_t height_;
   std::vector<Color> addressable_light_buffer_;
-  optional<std::string> last_effect_;
+  optional<uint32_t> last_effect_index_;
   optional<std::function<int(int, int)>> pixel_mapper_f_;
 };
 }  // namespace addressable_light

esphome/components/alarm_control_panel/alarm_control_panel.cpp

@@ -8,8 +8,7 @@
 #include "esphome/core/helpers.h"
 #include "esphome/core/log.h"
 
-namespace esphome {
-namespace alarm_control_panel {
+namespace esphome::alarm_control_panel {
 
 static const char *const TAG = "alarm_control_panel";
 
@@ -115,5 +114,4 @@ void AlarmControlPanel::disarm(optional<std::string> code) {
   call.perform();
 }
 
-}  // namespace alarm_control_panel
-}  // namespace esphome
+}  // namespace esphome::alarm_control_panel

esphome/components/alarm_control_panel/alarm_control_panel.h

@@ -1,7 +1,5 @@
 #pragma once
 
-#include <map>
-
 #include "alarm_control_panel_call.h"
 #include "alarm_control_panel_state.h"
 
@@ -9,8 +7,7 @@
 #include "esphome/core/entity_base.h"
 #include "esphome/core/log.h"
 
-namespace esphome {
-namespace alarm_control_panel {
+namespace esphome::alarm_control_panel {
 
 enum AlarmControlPanelFeature : uint8_t {
   // Matches Home Assistant values
@@ -141,5 +138,4 @@ class AlarmControlPanel : public EntityBase {
   LazyCallbackManager<void()> ready_callback_{};
 };
 
-}  // namespace alarm_control_panel
-}  // namespace esphome
+}  // namespace esphome::alarm_control_panel

esphome/components/alarm_control_panel/alarm_control_panel_call.cpp

@@ -4,8 +4,7 @@
 
 #include "esphome/core/log.h"
 
-namespace esphome {
-namespace alarm_control_panel {
+namespace esphome::alarm_control_panel {
 
 static const char *const TAG = "alarm_control_panel";
 
@@ -99,5 +98,4 @@ void AlarmControlPanelCall::perform() {
   }
 }
 
-}  // namespace alarm_control_panel
-}  // namespace esphome
+}  // namespace esphome::alarm_control_panel

esphome/components/alarm_control_panel/alarm_control_panel_call.h

@@ -6,8 +6,7 @@
 
 #include "esphome/core/helpers.h"
 
-namespace esphome {
-namespace alarm_control_panel {
+namespace esphome::alarm_control_panel {
 
 class AlarmControlPanel;
 
@@ -36,5 +35,4 @@ class AlarmControlPanelCall {
   void validate_();
 };
 
-}  // namespace alarm_control_panel
-}  // namespace esphome
+}  // namespace esphome::alarm_control_panel

esphome/components/alarm_control_panel/alarm_control_panel_state.cpp

@@ -1,7 +1,6 @@
 #include "alarm_control_panel_state.h"
 
-namespace esphome {
-namespace alarm_control_panel {
+namespace esphome::alarm_control_panel {
 
 const LogString *alarm_control_panel_state_to_string(AlarmControlPanelState state) {
   switch (state) {
@@ -30,5 +29,4 @@ const LogString *alarm_control_panel_state_to_string(AlarmControlPanelState stat
   }
 }
 
-}  // namespace alarm_control_panel
-}  // namespace esphome
+}  // namespace esphome::alarm_control_panel

esphome/components/alarm_control_panel/alarm_control_panel_state.h

@@ -3,8 +3,7 @@
 #include <cstdint>
 #include "esphome/core/log.h"
 
-namespace esphome {
-namespace alarm_control_panel {
+namespace esphome::alarm_control_panel {
 
 enum AlarmControlPanelState : uint8_t {
   ACP_STATE_DISARMED = 0,
@@ -25,5 +24,4 @@ enum AlarmControlPanelState : uint8_t {
  */
 const LogString *alarm_control_panel_state_to_string(AlarmControlPanelState state);
 
-}  // namespace alarm_control_panel
-}  // namespace esphome
+}  // namespace esphome::alarm_control_panel

esphome/components/alarm_control_panel/automation.h

@@ -3,8 +3,7 @@
 #include "esphome/core/automation.h"
 #include "alarm_control_panel.h"
 
-namespace esphome {
-namespace alarm_control_panel {
+namespace esphome::alarm_control_panel {
 
 /// Trigger on any state change
 class StateTrigger : public Trigger<> {
@@ -165,5 +164,4 @@ template<typename... Ts> class AlarmControlPanelCondition : public Condition<Ts.
   AlarmControlPanel *parent_;
 };
 
-}  // namespace alarm_control_panel
-}  // namespace esphome
+}  // namespace esphome::alarm_control_panel

esphome/components/api/api.proto

@@ -102,7 +102,7 @@ message HelloRequest {
   // For example "Home Assistant"
   // Not strictly necessary to send but nice for debugging
   // purposes.
-  string client_info = 1 [(pointer_to_buffer) = true];
+  string client_info = 1;
   uint32 api_version_major = 2;
   uint32 api_version_minor = 3;
 }
@@ -139,7 +139,7 @@ message AuthenticationRequest {
   option (ifdef) = "USE_API_PASSWORD";
 
   // The password to log in with
-  string password = 1 [(pointer_to_buffer) = true];
+  string password = 1;
 }
 
 // Confirmation of successful connection. After this the connection is available for all traffic.
@@ -477,7 +477,7 @@ message FanCommandRequest {
   bool has_speed_level = 10;
   int32 speed_level = 11;
   bool has_preset_mode = 12;
-  string preset_mode = 13 [(pointer_to_buffer) = true];
+  string preset_mode = 13;
   uint32 device_id = 14 [(field_ifdef) = "USE_DEVICES"];
 }
 
@@ -579,7 +579,7 @@ message LightCommandRequest {
   bool has_flash_length = 16;
   uint32 flash_length = 17;
   bool has_effect = 18;
-  string effect = 19 [(pointer_to_buffer) = true];
+  string effect = 19;
   uint32 device_id = 28 [(field_ifdef) = "USE_DEVICES"];
 }
 
@@ -747,7 +747,7 @@ message NoiseEncryptionSetKeyRequest {
   option (source) = SOURCE_CLIENT;
   option (ifdef) = "USE_API_NOISE";
 
-  bytes key = 1 [(pointer_to_buffer) = true];
+  bytes key = 1;
 }
 
 message NoiseEncryptionSetKeyResponse {
@@ -796,7 +796,7 @@ message HomeassistantActionResponse {
   uint32 call_id = 1; // Matches the call_id from HomeassistantActionRequest
   bool success = 2; // Whether the service call succeeded
   string error_message = 3; // Error message if success = false
-  bytes response_data = 4 [(pointer_to_buffer) = true, (field_ifdef) = "USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON"];
+  bytes response_data = 4 [(field_ifdef) = "USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON"];
 }
 
 // ==================== IMPORT HOME ASSISTANT STATES ====================
@@ -824,9 +824,9 @@ message HomeAssistantStateResponse {
   option (no_delay) = true;
   option (ifdef) = "USE_API_HOMEASSISTANT_STATES";
 
-  string entity_id = 1 [(pointer_to_buffer) = true];
-  string state = 2 [(pointer_to_buffer) = true];
-  string attribute = 3 [(pointer_to_buffer) = true];
+  string entity_id = 1;
+  string state = 2;
+  string attribute = 3;
 }
 
 // ==================== IMPORT TIME ====================
@@ -841,7 +841,7 @@ message GetTimeResponse {
   option (no_delay) = true;
 
   fixed32 epoch_seconds = 1;
-  string timezone = 2 [(pointer_to_buffer) = true];
+  string timezone = 2;
 }
 
 // ==================== USER-DEFINES SERVICES ====================
@@ -1091,11 +1091,11 @@ message ClimateCommandRequest {
   bool has_swing_mode = 14;
   ClimateSwingMode swing_mode = 15;
   bool has_custom_fan_mode = 16;
-  string custom_fan_mode = 17 [(pointer_to_buffer) = true];
+  string custom_fan_mode = 17;
   bool has_preset = 18;
   ClimatePreset preset = 19;
   bool has_custom_preset = 20;
-  string custom_preset = 21 [(pointer_to_buffer) = true];
+  string custom_preset = 21;
   bool has_target_humidity = 22;
   float target_humidity = 23;
   uint32 device_id = 24 [(field_ifdef) = "USE_DEVICES"];
@@ -1274,7 +1274,7 @@ message SelectCommandRequest {
   option (base_class) = "CommandProtoMessage";
 
   fixed32 key = 1;
-  string state = 2 [(pointer_to_buffer) = true];
+  string state = 2;
   uint32 device_id = 3 [(field_ifdef) = "USE_DEVICES"];
 }
 
@@ -1292,7 +1292,7 @@ message ListEntitiesSirenResponse {
 
   string icon = 5 [(field_ifdef) = "USE_ENTITY_ICON"];
   bool disabled_by_default = 6;
-  repeated string tones = 7;
+  repeated string tones = 7 [(container_pointer_no_template) = "FixedVector<const char *>"];
   bool supports_duration = 8;
   bool supports_volume = 9;
   EntityCategory entity_category = 10;
@@ -1692,7 +1692,7 @@ message BluetoothGATTWriteRequest {
   uint32 handle = 2;
   bool response = 3;
 
-  bytes data = 4 [(pointer_to_buffer) = true];
+  bytes data = 4;
 }
 
 message BluetoothGATTReadDescriptorRequest {
@@ -1712,7 +1712,7 @@ message BluetoothGATTWriteDescriptorRequest {
   uint64 address = 1;
   uint32 handle = 2;
 
-  bytes data = 3 [(pointer_to_buffer) = true];
+  bytes data = 3;
 }
 
 message BluetoothGATTNotifyRequest {
@@ -1937,7 +1937,7 @@ message VoiceAssistantAudio {
   option (source) = SOURCE_BOTH;
   option (ifdef) = "USE_VOICE_ASSISTANT";
 
-  bytes data = 1;
+  bytes data = 1 [(pointer_to_buffer) = true];
   bool end = 2;
 }
 

esphome/components/api/api_connection.cpp

@@ -101,16 +101,14 @@ APIConnection::APIConnection(std::unique_ptr<socket::Socket> sock, APIServer *pa
 #if defined(USE_API_PLAINTEXT) && defined(USE_API_NOISE)
   auto &noise_ctx = parent->get_noise_ctx();
   if (noise_ctx.has_psk()) {
-    this->helper_ =
-        std::unique_ptr<APIFrameHelper>{new APINoiseFrameHelper(std::move(sock), noise_ctx, &this->client_info_)};
+    this->helper_ = std::unique_ptr<APIFrameHelper>{new APINoiseFrameHelper(std::move(sock), noise_ctx)};
   } else {
-    this->helper_ = std::unique_ptr<APIFrameHelper>{new APIPlaintextFrameHelper(std::move(sock), &this->client_info_)};
+    this->helper_ = std::unique_ptr<APIFrameHelper>{new APIPlaintextFrameHelper(std::move(sock))};
   }
 #elif defined(USE_API_PLAINTEXT)
-  this->helper_ = std::unique_ptr<APIFrameHelper>{new APIPlaintextFrameHelper(std::move(sock), &this->client_info_)};
+  this->helper_ = std::unique_ptr<APIFrameHelper>{new APIPlaintextFrameHelper(std::move(sock))};
 #elif defined(USE_API_NOISE)
-  this->helper_ = std::unique_ptr<APIFrameHelper>{
-      new APINoiseFrameHelper(std::move(sock), parent->get_noise_ctx(), &this->client_info_)};
+  this->helper_ = std::unique_ptr<APIFrameHelper>{new APINoiseFrameHelper(std::move(sock), parent->get_noise_ctx())};
 #else
 #error "No frame helper defined"
 #endif
@@ -133,8 +131,8 @@ void APIConnection::start() {
   }
   // Initialize client name with peername (IP address) until Hello message provides actual name
   char peername[socket::PEERNAME_MAX_LEN];
-  this->helper_->getpeername_to(peername);
-  this->client_info_.name = peername;
+  size_t len = this->helper_->getpeername_to(peername);
+  this->helper_->set_client_name(peername, len);
 }
 
 APIConnection::~APIConnection() {
@@ -474,7 +472,7 @@ void APIConnection::fan_command(const FanCommandRequest &msg) {
   if (msg.has_direction)
     call.set_direction(static_cast<fan::FanDirection>(msg.direction));
   if (msg.has_preset_mode)
-    call.set_preset_mode(reinterpret_cast<const char *>(msg.preset_mode), msg.preset_mode_len);
+    call.set_preset_mode(msg.preset_mode.c_str(), msg.preset_mode.size());
   call.perform();
 }
 #endif
@@ -560,7 +558,7 @@ void APIConnection::light_command(const LightCommandRequest &msg) {
   if (msg.has_flash_length)
     call.set_flash_length(msg.flash_length);
   if (msg.has_effect)
-    call.set_effect(reinterpret_cast<const char *>(msg.effect), msg.effect_len);
+    call.set_effect(msg.effect.c_str(), msg.effect.size());
   call.perform();
 }
 #endif
@@ -739,11 +737,11 @@ void APIConnection::climate_command(const ClimateCommandRequest &msg) {
   if (msg.has_fan_mode)
     call.set_fan_mode(static_cast<climate::ClimateFanMode>(msg.fan_mode));
   if (msg.has_custom_fan_mode)
-    call.set_fan_mode(reinterpret_cast<const char *>(msg.custom_fan_mode), msg.custom_fan_mode_len);
+    call.set_fan_mode(msg.custom_fan_mode.c_str(), msg.custom_fan_mode.size());
   if (msg.has_preset)
     call.set_preset(static_cast<climate::ClimatePreset>(msg.preset));
   if (msg.has_custom_preset)
-    call.set_preset(reinterpret_cast<const char *>(msg.custom_preset), msg.custom_preset_len);
+    call.set_preset(msg.custom_preset.c_str(), msg.custom_preset.size());
   if (msg.has_swing_mode)
     call.set_swing_mode(static_cast<climate::ClimateSwingMode>(msg.swing_mode));
   call.perform();
@@ -932,7 +930,7 @@ uint16_t APIConnection::try_send_select_info(EntityBase *entity, APIConnection *
 }
 void APIConnection::select_command(const SelectCommandRequest &msg) {
   ENTITY_COMMAND_MAKE_CALL(select::Select, select, select)
-  call.set_option(reinterpret_cast<const char *>(msg.state), msg.state_len);
+  call.set_option(msg.state.c_str(), msg.state.size());
   call.perform();
 }
 #endif
@@ -1154,9 +1152,8 @@ void APIConnection::on_get_time_response(const GetTimeResponse &value) {
   if (homeassistant::global_homeassistant_time != nullptr) {
     homeassistant::global_homeassistant_time->set_epoch_time(value.epoch_seconds);
 #ifdef USE_TIME_TIMEZONE
-    if (value.timezone_len > 0) {
-      homeassistant::global_homeassistant_time->set_timezone(reinterpret_cast<const char *>(value.timezone),
-                                                             value.timezone_len);
+    if (!value.timezone.empty()) {
+      homeassistant::global_homeassistant_time->set_timezone(value.timezone.c_str(), value.timezone.size());
     }
 #endif
   }
@@ -1508,8 +1505,10 @@ void APIConnection::complete_authentication_() {
   this->flags_.connection_state = static_cast<uint8_t>(ConnectionState::AUTHENTICATED);
   this->log_client_(ESPHOME_LOG_LEVEL_DEBUG, LOG_STR("connected"));
 #ifdef USE_API_CLIENT_CONNECTED_TRIGGER
-  // Trigger expects std::string, get fresh peername from socket
-  this->parent_->get_client_connected_trigger()->trigger(this->client_info_.name, this->helper_->getpeername());
+  char peername_buf[socket::PEERNAME_MAX_LEN];
+  this->helper_->getpeername_to(peername_buf);
+  this->parent_->get_client_connected_trigger()->trigger(std::string(this->helper_->get_client_name()),
+                                                         std::string(peername_buf));
 #endif
 #ifdef USE_HOMEASSISTANT_TIME
   if (homeassistant::global_homeassistant_time != nullptr) {
@@ -1524,17 +1523,18 @@ void APIConnection::complete_authentication_() {
 }
 
 bool APIConnection::send_hello_response(const HelloRequest &msg) {
-  this->client_info_.name.assign(reinterpret_cast<const char *>(msg.client_info), msg.client_info_len);
+  // Copy client name with truncation if needed (set_client_name handles truncation)
+  this->helper_->set_client_name(msg.client_info.c_str(), msg.client_info.size());
   this->client_api_version_major_ = msg.api_version_major;
   this->client_api_version_minor_ = msg.api_version_minor;
   char peername[socket::PEERNAME_MAX_LEN];
   this->helper_->getpeername_to(peername);
-  ESP_LOGV(TAG, "Hello from client: '%s' | %s | API Version %" PRIu32 ".%" PRIu32, this->client_info_.name.c_str(),
+  ESP_LOGV(TAG, "Hello from client: '%s' | %s | API Version %" PRIu32 ".%" PRIu32, this->helper_->get_client_name(),
            peername, this->client_api_version_major_, this->client_api_version_minor_);
 
   HelloResponse resp;
   resp.api_version_major = 1;
-  resp.api_version_minor = 13;
+  resp.api_version_minor = 14;
   // Send only the version string - the client only logs this for debugging and doesn't use it otherwise
   resp.set_server_info(ESPHOME_VERSION_REF);
   resp.set_name(StringRef(App.get_name()));
@@ -1553,7 +1553,7 @@ bool APIConnection::send_hello_response(const HelloRequest &msg) {
 bool APIConnection::send_authenticate_response(const AuthenticationRequest &msg) {
   AuthenticationResponse resp;
   // bool invalid_password = 1;
-  resp.invalid_password = !this->parent_->check_password(msg.password, msg.password_len);
+  resp.invalid_password = !this->parent_->check_password(msg.password.byte(), msg.password.size());
   if (!resp.invalid_password) {
     this->complete_authentication_();
   }
@@ -1696,28 +1696,37 @@ bool APIConnection::send_device_info_response(const DeviceInfoRequest &msg) {
 #ifdef USE_API_HOMEASSISTANT_STATES
 void APIConnection::on_home_assistant_state_response(const HomeAssistantStateResponse &msg) {
   // Skip if entity_id is empty (invalid message)
-  if (msg.entity_id_len == 0) {
+  if (msg.entity_id.empty()) {
     return;
   }
 
   for (auto &it : this->parent_->get_state_subs()) {
     // Compare entity_id: check length matches and content matches
     size_t entity_id_len = strlen(it.entity_id);
-    if (entity_id_len != msg.entity_id_len || memcmp(it.entity_id, msg.entity_id, msg.entity_id_len) != 0) {
+    if (entity_id_len != msg.entity_id.size() ||
+        memcmp(it.entity_id, msg.entity_id.c_str(), msg.entity_id.size()) != 0) {
       continue;
     }
 
     // Compare attribute: either both have matching attribute, or both have none
     size_t sub_attr_len = it.attribute != nullptr ? strlen(it.attribute) : 0;
-    if (sub_attr_len != msg.attribute_len ||
-        (sub_attr_len > 0 && memcmp(it.attribute, msg.attribute, sub_attr_len) != 0)) {
+    if (sub_attr_len != msg.attribute.size() ||
+        (sub_attr_len > 0 && memcmp(it.attribute, msg.attribute.c_str(), sub_attr_len) != 0)) {
       continue;
     }
 
-    // Create temporary string for callback (callback takes const std::string &)
-    // Handle empty state (nullptr with len=0)
-    std::string state(msg.state_len > 0 ? reinterpret_cast<const char *>(msg.state) : "", msg.state_len);
-    it.callback(state);
+    // Create null-terminated state for callback (parse_number needs null-termination)
+    // HA state max length is 255, so 256 byte buffer covers all cases
+    char state_buf[256];
+    size_t copy_len = msg.state_len;
+    if (copy_len >= sizeof(state_buf)) {
+      copy_len = sizeof(state_buf) - 1;  // Truncate to leave space for null terminator
+    }
+    if (copy_len > 0) {
+      memcpy(state_buf, msg.state, copy_len);
+    }
+    state_buf[copy_len] = '\0';
+    it.callback(StringRef(state_buf, copy_len));
   }
 }
 #endif
@@ -1752,20 +1761,20 @@ void APIConnection::execute_service(const ExecuteServiceRequest &msg) {
   // the action list. This ensures async actions (delays, waits) complete first.
 }
 #ifdef USE_API_USER_DEFINED_ACTION_RESPONSES
-void APIConnection::send_execute_service_response(uint32_t call_id, bool success, const std::string &error_message) {
+void APIConnection::send_execute_service_response(uint32_t call_id, bool success, StringRef error_message) {
   ExecuteServiceResponse resp;
   resp.call_id = call_id;
   resp.success = success;
-  resp.set_error_message(StringRef(error_message));
+  resp.set_error_message(error_message);
   this->send_message(resp, ExecuteServiceResponse::MESSAGE_TYPE);
 }
 #ifdef USE_API_USER_DEFINED_ACTION_RESPONSES_JSON
-void APIConnection::send_execute_service_response(uint32_t call_id, bool success, const std::string &error_message,
+void APIConnection::send_execute_service_response(uint32_t call_id, bool success, StringRef error_message,
                                                   const uint8_t *response_data, size_t response_data_len) {
   ExecuteServiceResponse resp;
   resp.call_id = call_id;
   resp.success = success;
-  resp.set_error_message(StringRef(error_message));
+  resp.set_error_message(error_message);
   resp.response_data = response_data;
   resp.response_data_len = response_data_len;
   this->send_message(resp, ExecuteServiceResponse::MESSAGE_TYPE);
@@ -2107,14 +2116,14 @@ void APIConnection::process_state_subscriptions_() {
 void APIConnection::log_client_(int level, const LogString *message) {
   char peername[socket::PEERNAME_MAX_LEN];
   this->helper_->getpeername_to(peername);
-  esp_log_printf_(level, TAG, __LINE__, ESPHOME_LOG_FORMAT("%s (%s): %s"), this->client_info_.name.c_str(), peername,
+  esp_log_printf_(level, TAG, __LINE__, ESPHOME_LOG_FORMAT("%s (%s): %s"), this->helper_->get_client_name(), peername,
                   LOG_STR_ARG(message));
 }
 
 void APIConnection::log_warning_(const LogString *message, APIError err) {
   char peername[socket::PEERNAME_MAX_LEN];
   this->helper_->getpeername_to(peername);
-  ESP_LOGW(TAG, "%s (%s): %s %s errno=%d", this->client_info_.name.c_str(), peername, LOG_STR_ARG(message),
+  ESP_LOGW(TAG, "%s (%s): %s %s errno=%d", this->helper_->get_client_name(), peername, LOG_STR_ARG(message),
            LOG_STR_ARG(api_error_to_logstr(err)), errno);
 }
 

esphome/components/api/api_connection.h

@@ -9,25 +9,20 @@
 #include "esphome/core/application.h"
 #include "esphome/core/component.h"
 #include "esphome/core/entity_base.h"
+#include "esphome/core/string_ref.h"
 
 #include <functional>
 #include <vector>
 
 namespace esphome::api {
 
-// Client information structure
-struct ClientInfo {
-  std::string name;  // Client name from Hello message
-  // Note: peername (IP address) is not stored here to save memory.
-  // Use helper_->getpeername_to() or helper_->getpeername() when needed.
-};
-
 // Keepalive timeout in milliseconds
 static constexpr uint32_t KEEPALIVE_TIMEOUT_MS = 60000;
 // Maximum number of entities to process in a single batch during initial state/info sending
-// This was increased from 20 to 24 after removing the unique_id field from entity info messages,
-// which reduced message sizes allowing more entities per batch without exceeding packet limits
-static constexpr size_t MAX_INITIAL_PER_BATCH = 24;
+// API 1.14+ clients compute object_id client-side, so messages are smaller and we can fit more per batch
+// TODO: Remove MAX_INITIAL_PER_BATCH_LEGACY before 2026.7.0 - all clients should support API 1.14 by then
+static constexpr size_t MAX_INITIAL_PER_BATCH_LEGACY = 24;  // For clients < API 1.14 (includes object_id)
+static constexpr size_t MAX_INITIAL_PER_BATCH = 34;         // For clients >= API 1.14 (no object_id)
 // Maximum number of packets to process in a single batch (platform-dependent)
 // This limit exists to prevent stack overflow from the PacketInfo array in process_batch_
 // Each PacketInfo is 8 bytes, so 64 * 8 = 512 bytes, 32 * 8 = 256 bytes
@@ -234,9 +229,9 @@ class APIConnection final : public APIServerConnection {
 #ifdef USE_API_USER_DEFINED_ACTIONS
   void execute_service(const ExecuteServiceRequest &msg) override;
 #ifdef USE_API_USER_DEFINED_ACTION_RESPONSES
-  void send_execute_service_response(uint32_t call_id, bool success, const std::string &error_message);
+  void send_execute_service_response(uint32_t call_id, bool success, StringRef error_message);
 #ifdef USE_API_USER_DEFINED_ACTION_RESPONSES_JSON
-  void send_execute_service_response(uint32_t call_id, bool success, const std::string &error_message,
+  void send_execute_service_response(uint32_t call_id, bool success, StringRef error_message,
                                      const uint8_t *response_data, size_t response_data_len);
 #endif  // USE_API_USER_DEFINED_ACTION_RESPONSES_JSON
 #endif  // USE_API_USER_DEFINED_ACTION_RESPONSES
@@ -290,13 +285,11 @@ class APIConnection final : public APIServerConnection {
   bool try_to_clear_buffer(bool log_out_of_space);
   bool send_buffer(ProtoWriteBuffer buffer, uint8_t message_type) override;
 
-  const std::string &get_name() const { return this->client_info_.name; }
+  const char *get_name() const { return this->helper_->get_client_name(); }
   /// Get peer name (IP address) into a stack buffer - avoids heap allocation
   size_t get_peername_to(std::span<char, socket::PEERNAME_MAX_LEN> buf) const {
     return this->helper_->getpeername_to(buf);
   }
-  /// Get peer name as std::string - use sparingly, allocates on heap
-  std::string get_peername() const { return this->helper_->getpeername(); }
 
  protected:
   // Helper function to handle authentication completion
@@ -329,10 +322,16 @@ class APIConnection final : public APIServerConnection {
                                               APIConnection *conn, uint32_t remaining_size, bool is_single) {
     // Set common fields that are shared by all entity types
     msg.key = entity->get_object_id_hash();
-    // Get object_id with zero heap allocation
-    // Static case returns direct reference, dynamic case uses buffer
+
+    // API 1.14+ clients compute object_id client-side from the entity name
+    // For older clients, we must send object_id for backward compatibility
+    // See: https://github.com/esphome/backlog/issues/76
+    // TODO: Remove this backward compat code before 2026.7.0 - all clients should support API 1.14 by then
+    // Buffer must remain in scope until encode_message_to_buffer is called
     char object_id_buf[OBJECT_ID_MAX_LEN];
-    msg.set_object_id(entity->get_object_id_to(object_id_buf));
+    if (!conn->client_supports_api_version(1, 14)) {
+      msg.set_object_id(entity->get_object_id_to(object_id_buf));
+    }
 
     if (entity->has_own_name()) {
       msg.set_name(entity->get_name());
@@ -355,16 +354,24 @@ class APIConnection final : public APIServerConnection {
   inline bool check_voice_assistant_api_connection_() const;
 #endif
 
+  // Get the max batch size based on client API version
+  // API 1.14+ clients don't receive object_id, so messages are smaller and more fit per batch
+  // TODO: Remove this method before 2026.7.0 and use MAX_INITIAL_PER_BATCH directly
+  size_t get_max_batch_size_() const {
+    return this->client_supports_api_version(1, 14) ? MAX_INITIAL_PER_BATCH : MAX_INITIAL_PER_BATCH_LEGACY;
+  }
+
   // Helper method to process multiple entities from an iterator in a batch
   template<typename Iterator> void process_iterator_batch_(Iterator &iterator) {
     size_t initial_size = this->deferred_batch_.size();
-    while (!iterator.completed() && (this->deferred_batch_.size() - initial_size) < MAX_INITIAL_PER_BATCH) {
+    size_t max_batch = this->get_max_batch_size_();
+    while (!iterator.completed() && (this->deferred_batch_.size() - initial_size) < max_batch) {
       iterator.advance();
     }
 
     // If the batch is full, process it immediately
     // Note: iterator.advance() already calls schedule_batch_() via schedule_message_()
-    if (this->deferred_batch_.size() >= MAX_INITIAL_PER_BATCH) {
+    if (this->deferred_batch_.size() >= max_batch) {
       this->process_batch_();
     }
   }
@@ -528,10 +535,7 @@ class APIConnection final : public APIServerConnection {
   std::unique_ptr<camera::CameraImageReader> image_reader_;
 #endif
 
-  // Group 3: Client info struct (24 bytes on 32-bit: 2 strings × 12 bytes each)
-  ClientInfo client_info_;
-
-  // Group 4: 4-byte types
+  // Group 3: 4-byte types
   uint32_t last_traffic_;
 #ifdef USE_API_HOMEASSISTANT_STATES
   int state_subs_at_ = -1;

esphome/components/api/api_frame_helper.cpp

@@ -1,6 +1,5 @@
 #include "api_frame_helper.h"
 #ifdef USE_API
-#include "api_connection.h"  // For ClientInfo struct
 #include "esphome/core/application.h"
 #include "esphome/core/hal.h"
 #include "esphome/core/helpers.h"
@@ -13,20 +12,34 @@ namespace esphome::api {
 
 static const char *const TAG = "api.frame_helper";
 
+// Maximum bytes to log in hex format (168 * 3 = 504, under TX buffer size of 512)
+static constexpr size_t API_MAX_LOG_BYTES = 168;
+
 #if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERY_VERBOSE
 #define HELPER_LOG(msg, ...) \
   do { \
     char peername__[socket::PEERNAME_MAX_LEN]; \
     this->socket_->getpeername_to(peername__); \
-    ESP_LOGVV(TAG, "%s (%s): " msg, this->client_info_->name.c_str(), peername__, ##__VA_ARGS__); \
+    ESP_LOGVV(TAG, "%s (%s): " msg, this->client_name_, peername__, ##__VA_ARGS__); \
   } while (0)
 #else
 #define HELPER_LOG(msg, ...) ((void) 0)
 #endif
 
 #ifdef HELPER_LOG_PACKETS
-#define LOG_PACKET_RECEIVED(buffer) ESP_LOGVV(TAG, "Received frame: %s", format_hex_pretty(buffer).c_str())
-#define LOG_PACKET_SENDING(data, len) ESP_LOGVV(TAG, "Sending raw: %s", format_hex_pretty(data, len).c_str())
+#define LOG_PACKET_RECEIVED(buffer) \
+  do { \
+    char hex_buf_[format_hex_pretty_size(API_MAX_LOG_BYTES)]; \
+    ESP_LOGVV(TAG, "Received frame: %s", \
+              format_hex_pretty_to(hex_buf_, (buffer).data(), \
+                                   (buffer).size() < API_MAX_LOG_BYTES ? (buffer).size() : API_MAX_LOG_BYTES)); \
+  } while (0)
+#define LOG_PACKET_SENDING(data, len) \
+  do { \
+    char hex_buf_[format_hex_pretty_size(API_MAX_LOG_BYTES)]; \
+    ESP_LOGVV(TAG, "Sending raw: %s", \
+              format_hex_pretty_to(hex_buf_, data, (len) < API_MAX_LOG_BYTES ? (len) : API_MAX_LOG_BYTES)); \
+  } while (0)
 #else
 #define LOG_PACKET_RECEIVED(buffer) ((void) 0)
 #define LOG_PACKET_SENDING(data, len) ((void) 0)

esphome/components/api/api_frame_helper.h

@@ -29,11 +29,11 @@ static constexpr uint16_t MAX_MESSAGE_SIZE = 8192;  // 8 KiB for ESP8266
 static constexpr uint16_t MAX_MESSAGE_SIZE = 32768;  // 32 KiB for ESP32 and other platforms
 #endif
 
-// Forward declaration
-struct ClientInfo;
-
 class ProtoWriteBuffer;
 
+// Max client name length (e.g., "Home Assistant 2026.1.0.dev0" = 28 chars)
+static constexpr size_t CLIENT_INFO_NAME_MAX_LEN = 32;
+
 struct ReadPacketBuffer {
   const uint8_t *data;  // Points directly into frame helper's rx_buf_ (valid until next read_packet call)
   uint16_t data_len;
@@ -82,14 +82,21 @@ const LogString *api_error_to_logstr(APIError err);
 class APIFrameHelper {
  public:
   APIFrameHelper() = default;
-  explicit APIFrameHelper(std::unique_ptr<socket::Socket> socket, const ClientInfo *client_info)
-      : socket_(std::move(socket)), client_info_(client_info) {}
+  explicit APIFrameHelper(std::unique_ptr<socket::Socket> socket) : socket_(std::move(socket)) {}
+
+  // Get client name (null-terminated)
+  const char *get_client_name() const { return this->client_name_; }
+  // Set client name from buffer with length (truncates if needed)
+  void set_client_name(const char *name, size_t len) {
+    size_t copy_len = std::min(len, sizeof(this->client_name_) - 1);
+    memcpy(this->client_name_, name, copy_len);
+    this->client_name_[copy_len] = '\0';
+  }
   virtual ~APIFrameHelper() = default;
   virtual APIError init() = 0;
   virtual APIError loop();
   virtual APIError read_packet(ReadPacketBuffer *buffer) = 0;
   bool can_write_without_blocking() { return this->state_ == State::DATA && this->tx_buf_count_ == 0; }
-  std::string getpeername() { return socket_->getpeername(); }
   int getpeername(struct sockaddr *addr, socklen_t *addrlen) { return socket_->getpeername(addr, addrlen); }
   size_t getpeername_to(std::span<char, socket::PEERNAME_MAX_LEN> buf) { return socket_->getpeername_to(buf); }
   APIError close() {
@@ -190,9 +197,8 @@ class APIFrameHelper {
   std::vector<struct iovec> reusable_iovs_;
   std::vector<uint8_t> rx_buf_;
 
-  // Pointer to client info (4 bytes on 32-bit)
-  // Note: The pointed-to ClientInfo object must outlive this APIFrameHelper instance.
-  const ClientInfo *client_info_{nullptr};
+  // Client name buffer - stores name from Hello message or initial peername
+  char client_name_[CLIENT_INFO_NAME_MAX_LEN]{};
 
   // Group smaller types together
   uint16_t rx_buf_len_ = 0;

esphome/components/api/api_frame_helper_noise.cpp

@@ -24,20 +24,34 @@ static const char *const PROLOGUE_INIT = "NoiseAPIInit";
 #endif
 static constexpr size_t PROLOGUE_INIT_LEN = 12;  // strlen("NoiseAPIInit")
 
+// Maximum bytes to log in hex format (168 * 3 = 504, under TX buffer size of 512)
+static constexpr size_t API_MAX_LOG_BYTES = 168;
+
 #if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERY_VERBOSE
 #define HELPER_LOG(msg, ...) \
   do { \
     char peername__[socket::PEERNAME_MAX_LEN]; \
     this->socket_->getpeername_to(peername__); \
-    ESP_LOGVV(TAG, "%s (%s): " msg, this->client_info_->name.c_str(), peername__, ##__VA_ARGS__); \
+    ESP_LOGVV(TAG, "%s (%s): " msg, this->client_name_, peername__, ##__VA_ARGS__); \
   } while (0)
 #else
 #define HELPER_LOG(msg, ...) ((void) 0)
 #endif
 
 #ifdef HELPER_LOG_PACKETS
-#define LOG_PACKET_RECEIVED(buffer) ESP_LOGVV(TAG, "Received frame: %s", format_hex_pretty(buffer).c_str())
-#define LOG_PACKET_SENDING(data, len) ESP_LOGVV(TAG, "Sending raw: %s", format_hex_pretty(data, len).c_str())
+#define LOG_PACKET_RECEIVED(buffer) \
+  do { \
+    char hex_buf_[format_hex_pretty_size(API_MAX_LOG_BYTES)]; \
+    ESP_LOGVV(TAG, "Received frame: %s", \
+              format_hex_pretty_to(hex_buf_, (buffer).data(), \
+                                   (buffer).size() < API_MAX_LOG_BYTES ? (buffer).size() : API_MAX_LOG_BYTES)); \
+  } while (0)
+#define LOG_PACKET_SENDING(data, len) \
+  do { \
+    char hex_buf_[format_hex_pretty_size(API_MAX_LOG_BYTES)]; \
+    ESP_LOGVV(TAG, "Sending raw: %s", \
+              format_hex_pretty_to(hex_buf_, data, (len) < API_MAX_LOG_BYTES ? (len) : API_MAX_LOG_BYTES)); \
+  } while (0)
 #else
 #define LOG_PACKET_RECEIVED(buffer) ((void) 0)
 #define LOG_PACKET_SENDING(data, len) ((void) 0)

esphome/components/api/api_frame_helper_noise.h

@@ -9,8 +9,8 @@ namespace esphome::api {
 
 class APINoiseFrameHelper final : public APIFrameHelper {
  public:
-  APINoiseFrameHelper(std::unique_ptr<socket::Socket> socket, APINoiseContext &ctx, const ClientInfo *client_info)
-      : APIFrameHelper(std::move(socket), client_info), ctx_(ctx) {
+  APINoiseFrameHelper(std::unique_ptr<socket::Socket> socket, APINoiseContext &ctx)
+      : APIFrameHelper(std::move(socket)), ctx_(ctx) {
     // Noise header structure:
     // Pos 0: indicator (0x01)
     // Pos 1-2: encrypted payload size (16-bit big-endian)

esphome/components/api/api_frame_helper_plaintext.cpp

@@ -1,7 +1,6 @@
 #include "api_frame_helper_plaintext.h"
 #ifdef USE_API
 #ifdef USE_API_PLAINTEXT
-#include "api_connection.h"  // For ClientInfo struct
 #include "esphome/core/application.h"
 #include "esphome/core/hal.h"
 #include "esphome/core/helpers.h"
@@ -18,20 +17,34 @@ namespace esphome::api {
 
 static const char *const TAG = "api.plaintext";
 
+// Maximum bytes to log in hex format (168 * 3 = 504, under TX buffer size of 512)
+static constexpr size_t API_MAX_LOG_BYTES = 168;
+
 #if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERY_VERBOSE
 #define HELPER_LOG(msg, ...) \
   do { \
     char peername__[socket::PEERNAME_MAX_LEN]; \
     this->socket_->getpeername_to(peername__); \
-    ESP_LOGVV(TAG, "%s (%s): " msg, this->client_info_->name.c_str(), peername__, ##__VA_ARGS__); \
+    ESP_LOGVV(TAG, "%s (%s): " msg, this->client_name_, peername__, ##__VA_ARGS__); \
   } while (0)
 #else
 #define HELPER_LOG(msg, ...) ((void) 0)
 #endif
 
 #ifdef HELPER_LOG_PACKETS
-#define LOG_PACKET_RECEIVED(buffer) ESP_LOGVV(TAG, "Received frame: %s", format_hex_pretty(buffer).c_str())
-#define LOG_PACKET_SENDING(data, len) ESP_LOGVV(TAG, "Sending raw: %s", format_hex_pretty(data, len).c_str())
+#define LOG_PACKET_RECEIVED(buffer) \
+  do { \
+    char hex_buf_[format_hex_pretty_size(API_MAX_LOG_BYTES)]; \
+    ESP_LOGVV(TAG, "Received frame: %s", \
+              format_hex_pretty_to(hex_buf_, (buffer).data(), \
+                                   (buffer).size() < API_MAX_LOG_BYTES ? (buffer).size() : API_MAX_LOG_BYTES)); \
+  } while (0)
+#define LOG_PACKET_SENDING(data, len) \
+  do { \
+    char hex_buf_[format_hex_pretty_size(API_MAX_LOG_BYTES)]; \
+    ESP_LOGVV(TAG, "Sending raw: %s", \
+              format_hex_pretty_to(hex_buf_, data, (len) < API_MAX_LOG_BYTES ? (len) : API_MAX_LOG_BYTES)); \
+  } while (0)
 #else
 #define LOG_PACKET_RECEIVED(buffer) ((void) 0)
 #define LOG_PACKET_SENDING(data, len) ((void) 0)

esphome/components/api/api_frame_helper_plaintext.h

@@ -7,8 +7,7 @@ namespace esphome::api {
 
 class APIPlaintextFrameHelper final : public APIFrameHelper {
  public:
-  APIPlaintextFrameHelper(std::unique_ptr<socket::Socket> socket, const ClientInfo *client_info)
-      : APIFrameHelper(std::move(socket), client_info) {
+  explicit APIPlaintextFrameHelper(std::unique_ptr<socket::Socket> socket) : APIFrameHelper(std::move(socket)) {
     // Plaintext header structure (worst case):
     // Pos 0: indicator (0x00)
     // Pos 1-3: payload size varint (up to 3 bytes)

esphome/components/api/api_pb2.cpp

@@ -23,9 +23,7 @@ bool HelloRequest::decode_varint(uint32_t field_id, ProtoVarInt value) {
 bool HelloRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 1: {
-      // Use raw data directly to avoid allocation
-      this->client_info = value.data();
-      this->client_info_len = value.size();
+      this->client_info = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
     }
     default:
@@ -49,9 +47,7 @@ void HelloResponse::calculate_size(ProtoSize &size) const {
 bool AuthenticationRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 1: {
-      // Use raw data directly to avoid allocation
-      this->password = value.data();
-      this->password_len = value.size();
+      this->password = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
     }
     default:
@@ -448,9 +444,7 @@ bool FanCommandRequest::decode_varint(uint32_t field_id, ProtoVarInt value) {
 bool FanCommandRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 13: {
-      // Use raw data directly to avoid allocation
-      this->preset_mode = value.data();
-      this->preset_mode_len = value.size();
+      this->preset_mode = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
     }
     default:
@@ -615,9 +609,7 @@ bool LightCommandRequest::decode_varint(uint32_t field_id, ProtoVarInt value) {
 bool LightCommandRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 19: {
-      // Use raw data directly to avoid allocation
-      this->effect = value.data();
-      this->effect_len = value.size();
+      this->effect = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
     }
     default:
@@ -859,7 +851,6 @@ void SubscribeLogsResponse::calculate_size(ProtoSize &size) const {
 bool NoiseEncryptionSetKeyRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 1: {
-      // Use raw data directly to avoid allocation
       this->key = value.data();
       this->key_len = value.size();
       break;
@@ -936,12 +927,12 @@ bool HomeassistantActionResponse::decode_varint(uint32_t field_id, ProtoVarInt v
 }
 bool HomeassistantActionResponse::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 3:
-      this->error_message = value.as_string();
+    case 3: {
+      this->error_message = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
+    }
 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
     case 4: {
-      // Use raw data directly to avoid allocation
       this->response_data = value.data();
       this->response_data_len = value.size();
       break;
@@ -967,21 +958,15 @@ void SubscribeHomeAssistantStateResponse::calculate_size(ProtoSize &size) const
 bool HomeAssistantStateResponse::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 1: {
-      // Use raw data directly to avoid allocation
-      this->entity_id = value.data();
-      this->entity_id_len = value.size();
+      this->entity_id = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
     }
     case 2: {
-      // Use raw data directly to avoid allocation
-      this->state = value.data();
-      this->state_len = value.size();
+      this->state = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
     }
     case 3: {
-      // Use raw data directly to avoid allocation
-      this->attribute = value.data();
-      this->attribute_len = value.size();
+      this->attribute = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
     }
     default:
@@ -993,9 +978,7 @@ bool HomeAssistantStateResponse::decode_length(uint32_t field_id, ProtoLengthDel
 bool GetTimeResponse::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 2: {
-      // Use raw data directly to avoid allocation
-      this->timezone = value.data();
-      this->timezone_len = value.size();
+      this->timezone = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
     }
     default:
@@ -1060,9 +1043,10 @@ bool ExecuteServiceArgument::decode_varint(uint32_t field_id, ProtoVarInt value)
 }
 bool ExecuteServiceArgument::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 4:
-      this->string_ = value.as_string();
+    case 4: {
+      this->string_ = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
+    }
     case 9:
       this->string_array.push_back(value.as_string());
       break;
@@ -1153,7 +1137,7 @@ void ExecuteServiceResponse::calculate_size(ProtoSize &size) const {
   size.add_bool(1, this->success);
   size.add_length(1, this->error_message_ref_.size());
 #ifdef USE_API_USER_DEFINED_ACTION_RESPONSES_JSON
-  size.add_length(4, this->response_data_len);
+  size.add_length(1, this->response_data_len);
 #endif
 }
 #endif
@@ -1408,15 +1392,11 @@ bool ClimateCommandRequest::decode_varint(uint32_t field_id, ProtoVarInt value)
 bool ClimateCommandRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 17: {
-      // Use raw data directly to avoid allocation
-      this->custom_fan_mode = value.data();
-      this->custom_fan_mode_len = value.size();
+      this->custom_fan_mode = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
     }
     case 21: {
-      // Use raw data directly to avoid allocation
-      this->custom_preset = value.data();
-      this->custom_preset_len = value.size();
+      this->custom_preset = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
     }
     default:
@@ -1702,9 +1682,7 @@ bool SelectCommandRequest::decode_varint(uint32_t field_id, ProtoVarInt value) {
 bool SelectCommandRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 2: {
-      // Use raw data directly to avoid allocation
-      this->state = value.data();
-      this->state_len = value.size();
+      this->state = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
     }
     default:
@@ -1732,8 +1710,8 @@ void ListEntitiesSirenResponse::encode(ProtoWriteBuffer buffer) const {
   buffer.encode_string(5, this->icon_ref_);
 #endif
   buffer.encode_bool(6, this->disabled_by_default);
-  for (auto &it : this->tones) {
-    buffer.encode_string(7, it, true);
+  for (const char *it : *this->tones) {
+    buffer.encode_string(7, it, strlen(it), true);
   }
   buffer.encode_bool(8, this->supports_duration);
   buffer.encode_bool(9, this->supports_volume);
@@ -1750,9 +1728,9 @@ void ListEntitiesSirenResponse::calculate_size(ProtoSize &size) const {
   size.add_length(1, this->icon_ref_.size());
 #endif
   size.add_bool(1, this->disabled_by_default);
-  if (!this->tones.empty()) {
-    for (const auto &it : this->tones) {
-      size.add_length_force(1, it.size());
+  if (!this->tones->empty()) {
+    for (const char *it : *this->tones) {
+      size.add_length_force(1, strlen(it));
     }
   }
   size.add_bool(1, this->supports_duration);
@@ -1808,9 +1786,10 @@ bool SirenCommandRequest::decode_varint(uint32_t field_id, ProtoVarInt value) {
 }
 bool SirenCommandRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 5:
-      this->tone = value.as_string();
+    case 5: {
+      this->tone = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
+    }
     default:
       return false;
   }
@@ -1899,9 +1878,10 @@ bool LockCommandRequest::decode_varint(uint32_t field_id, ProtoVarInt value) {
 }
 bool LockCommandRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 4:
-      this->code = value.as_string();
+    case 4: {
+      this->code = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
+    }
     default:
       return false;
   }
@@ -2069,9 +2049,10 @@ bool MediaPlayerCommandRequest::decode_varint(uint32_t field_id, ProtoVarInt val
 }
 bool MediaPlayerCommandRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 7:
-      this->media_url = value.as_string();
+    case 7: {
+      this->media_url = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
+    }
     default:
       return false;
   }
@@ -2279,7 +2260,6 @@ bool BluetoothGATTWriteRequest::decode_varint(uint32_t field_id, ProtoVarInt val
 bool BluetoothGATTWriteRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 4: {
-      // Use raw data directly to avoid allocation
       this->data = value.data();
       this->data_len = value.size();
       break;
@@ -2318,7 +2298,6 @@ bool BluetoothGATTWriteDescriptorRequest::decode_varint(uint32_t field_id, Proto
 bool BluetoothGATTWriteDescriptorRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 3: {
-      // Use raw data directly to avoid allocation
       this->data = value.data();
       this->data_len = value.size();
       break;
@@ -2502,12 +2481,14 @@ bool VoiceAssistantResponse::decode_varint(uint32_t field_id, ProtoVarInt value)
 }
 bool VoiceAssistantEventData::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 1:
-      this->name = value.as_string();
+    case 1: {
+      this->name = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
-    case 2:
-      this->value = value.as_string();
+    }
+    case 2: {
+      this->value = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
+    }
     default:
       return false;
   }
@@ -2546,20 +2527,22 @@ bool VoiceAssistantAudio::decode_varint(uint32_t field_id, ProtoVarInt value) {
 }
 bool VoiceAssistantAudio::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 1:
-      this->data = value.as_string();
+    case 1: {
+      this->data = value.data();
+      this->data_len = value.size();
       break;
+    }
     default:
       return false;
   }
   return true;
 }
 void VoiceAssistantAudio::encode(ProtoWriteBuffer buffer) const {
-  buffer.encode_bytes(1, this->data_ptr_, this->data_len_);
+  buffer.encode_bytes(1, this->data, this->data_len);
   buffer.encode_bool(2, this->end);
 }
 void VoiceAssistantAudio::calculate_size(ProtoSize &size) const {
-  size.add_length(1, this->data_len_);
+  size.add_length(1, this->data_len);
   size.add_bool(1, this->end);
 }
 bool VoiceAssistantTimerEventResponse::decode_varint(uint32_t field_id, ProtoVarInt value) {
@@ -2583,12 +2566,14 @@ bool VoiceAssistantTimerEventResponse::decode_varint(uint32_t field_id, ProtoVar
 }
 bool VoiceAssistantTimerEventResponse::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 2:
-      this->timer_id = value.as_string();
+    case 2: {
+      this->timer_id = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
-    case 3:
-      this->name = value.as_string();
+    }
+    case 3: {
+      this->name = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
+    }
     default:
       return false;
   }
@@ -2606,15 +2591,18 @@ bool VoiceAssistantAnnounceRequest::decode_varint(uint32_t field_id, ProtoVarInt
 }
 bool VoiceAssistantAnnounceRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 1:
-      this->media_id = value.as_string();
+    case 1: {
+      this->media_id = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
-    case 2:
-      this->text = value.as_string();
+    }
+    case 2: {
+      this->text = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
-    case 3:
-      this->preannounce_media_id = value.as_string();
+    }
+    case 3: {
+      this->preannounce_media_id = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
+    }
     default:
       return false;
   }
@@ -2650,24 +2638,29 @@ bool VoiceAssistantExternalWakeWord::decode_varint(uint32_t field_id, ProtoVarIn
 }
 bool VoiceAssistantExternalWakeWord::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 1:
-      this->id = value.as_string();
+    case 1: {
+      this->id = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
-    case 2:
-      this->wake_word = value.as_string();
+    }
+    case 2: {
+      this->wake_word = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
+    }
     case 3:
       this->trained_languages.push_back(value.as_string());
       break;
-    case 4:
-      this->model_type = value.as_string();
+    case 4: {
+      this->model_type = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
-    case 6:
-      this->model_hash = value.as_string();
+    }
+    case 6: {
+      this->model_hash = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
-    case 7:
-      this->url = value.as_string();
+    }
+    case 7: {
+      this->url = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
+    }
     default:
       return false;
   }
@@ -2777,9 +2770,10 @@ bool AlarmControlPanelCommandRequest::decode_varint(uint32_t field_id, ProtoVarI
 }
 bool AlarmControlPanelCommandRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 3:
-      this->code = value.as_string();
+    case 3: {
+      this->code = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
+    }
     default:
       return false;
   }
@@ -2861,9 +2855,10 @@ bool TextCommandRequest::decode_varint(uint32_t field_id, ProtoVarInt value) {
 }
 bool TextCommandRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
-    case 2:
-      this->state = value.as_string();
+    case 2: {
+      this->state = StringRef(reinterpret_cast<const char *>(value.data()), value.size());
       break;
+    }
     default:
       return false;
   }
@@ -3331,7 +3326,6 @@ bool UpdateCommandRequest::decode_32bit(uint32_t field_id, Proto32Bit value) {
 bool ZWaveProxyFrame::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 1: {
-      // Use raw data directly to avoid allocation
       this->data = value.data();
       this->data_len = value.size();
       break;
@@ -3356,7 +3350,6 @@ bool ZWaveProxyRequest::decode_varint(uint32_t field_id, ProtoVarInt value) {
 bool ZWaveProxyRequest::decode_length(uint32_t field_id, ProtoLengthDelimited value) {
   switch (field_id) {
     case 2: {
-      // Use raw data directly to avoid allocation
       this->data = value.data();
       this->data_len = value.size();
       break;
@@ -3372,7 +3365,7 @@ void ZWaveProxyRequest::encode(ProtoWriteBuffer buffer) const {
 }
 void ZWaveProxyRequest::calculate_size(ProtoSize &size) const {
   size.add_uint32(1, static_cast<uint32_t>(this->type));
-  size.add_length(2, this->data_len);
+  size.add_length(1, this->data_len);
 }
 #endif
 

esphome/components/api/api_pb2.h

@@ -357,12 +357,11 @@ class CommandProtoMessage : public ProtoDecodableMessage {
 class HelloRequest final : public ProtoDecodableMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 1;
-  static constexpr uint8_t ESTIMATED_SIZE = 27;
+  static constexpr uint8_t ESTIMATED_SIZE = 17;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "hello_request"; }
 #endif
-  const uint8_t *client_info{nullptr};
-  uint16_t client_info_len{0};
+  StringRef client_info{};
   uint32_t api_version_major{0};
   uint32_t api_version_minor{0};
 #ifdef HAS_PROTO_MESSAGE_DUMP
@@ -398,12 +397,11 @@ class HelloResponse final : public ProtoMessage {
 class AuthenticationRequest final : public ProtoDecodableMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 3;
-  static constexpr uint8_t ESTIMATED_SIZE = 19;
+  static constexpr uint8_t ESTIMATED_SIZE = 9;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "authentication_request"; }
 #endif
-  const uint8_t *password{nullptr};
-  uint16_t password_len{0};
+  StringRef password{};
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif
@@ -784,7 +782,7 @@ class FanStateResponse final : public StateResponseProtoMessage {
 class FanCommandRequest final : public CommandProtoMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 31;
-  static constexpr uint8_t ESTIMATED_SIZE = 48;
+  static constexpr uint8_t ESTIMATED_SIZE = 38;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "fan_command_request"; }
 #endif
@@ -797,8 +795,7 @@ class FanCommandRequest final : public CommandProtoMessage {
   bool has_speed_level{false};
   int32_t speed_level{0};
   bool has_preset_mode{false};
-  const uint8_t *preset_mode{nullptr};
-  uint16_t preset_mode_len{0};
+  StringRef preset_mode{};
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif
@@ -860,7 +857,7 @@ class LightStateResponse final : public StateResponseProtoMessage {
 class LightCommandRequest final : public CommandProtoMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 32;
-  static constexpr uint8_t ESTIMATED_SIZE = 122;
+  static constexpr uint8_t ESTIMATED_SIZE = 112;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "light_command_request"; }
 #endif
@@ -889,8 +886,7 @@ class LightCommandRequest final : public CommandProtoMessage {
   bool has_flash_length{false};
   uint32_t flash_length{0};
   bool has_effect{false};
-  const uint8_t *effect{nullptr};
-  uint16_t effect_len{0};
+  StringRef effect{};
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif
@@ -1073,7 +1069,7 @@ class SubscribeLogsResponse final : public ProtoMessage {
 class NoiseEncryptionSetKeyRequest final : public ProtoDecodableMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 124;
-  static constexpr uint8_t ESTIMATED_SIZE = 19;
+  static constexpr uint8_t ESTIMATED_SIZE = 9;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "noise_encryption_set_key_request"; }
 #endif
@@ -1165,13 +1161,13 @@ class HomeassistantActionRequest final : public ProtoMessage {
 class HomeassistantActionResponse final : public ProtoDecodableMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 130;
-  static constexpr uint8_t ESTIMATED_SIZE = 34;
+  static constexpr uint8_t ESTIMATED_SIZE = 24;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "homeassistant_action_response"; }
 #endif
   uint32_t call_id{0};
   bool success{false};
-  std::string error_message{};
+  StringRef error_message{};
 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
   const uint8_t *response_data{nullptr};
   uint16_t response_data_len{0};
@@ -1222,16 +1218,13 @@ class SubscribeHomeAssistantStateResponse final : public ProtoMessage {
 class HomeAssistantStateResponse final : public ProtoDecodableMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 40;
-  static constexpr uint8_t ESTIMATED_SIZE = 57;
+  static constexpr uint8_t ESTIMATED_SIZE = 27;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "home_assistant_state_response"; }
 #endif
-  const uint8_t *entity_id{nullptr};
-  uint16_t entity_id_len{0};
-  const uint8_t *state{nullptr};
-  uint16_t state_len{0};
-  const uint8_t *attribute{nullptr};
-  uint16_t attribute_len{0};
+  StringRef entity_id{};
+  StringRef state{};
+  StringRef attribute{};
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif
@@ -1256,13 +1249,12 @@ class GetTimeRequest final : public ProtoMessage {
 class GetTimeResponse final : public ProtoDecodableMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 37;
-  static constexpr uint8_t ESTIMATED_SIZE = 24;
+  static constexpr uint8_t ESTIMATED_SIZE = 14;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "get_time_response"; }
 #endif
   uint32_t epoch_seconds{0};
-  const uint8_t *timezone{nullptr};
-  uint16_t timezone_len{0};
+  StringRef timezone{};
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif
@@ -1310,7 +1302,7 @@ class ExecuteServiceArgument final : public ProtoDecodableMessage {
   bool bool_{false};
   int32_t legacy_int{0};
   float float_{0.0f};
-  std::string string_{};
+  StringRef string_{};
   int32_t int_{0};
   FixedVector<bool> bool_array{};
   FixedVector<int32_t> int_array{};
@@ -1499,7 +1491,7 @@ class ClimateStateResponse final : public StateResponseProtoMessage {
 class ClimateCommandRequest final : public CommandProtoMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 48;
-  static constexpr uint8_t ESTIMATED_SIZE = 104;
+  static constexpr uint8_t ESTIMATED_SIZE = 84;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "climate_command_request"; }
 #endif
@@ -1516,13 +1508,11 @@ class ClimateCommandRequest final : public CommandProtoMessage {
   bool has_swing_mode{false};
   enums::ClimateSwingMode swing_mode{};
   bool has_custom_fan_mode{false};
-  const uint8_t *custom_fan_mode{nullptr};
-  uint16_t custom_fan_mode_len{0};
+  StringRef custom_fan_mode{};
   bool has_preset{false};
   enums::ClimatePreset preset{};
   bool has_custom_preset{false};
-  const uint8_t *custom_preset{nullptr};
-  uint16_t custom_preset_len{0};
+  StringRef custom_preset{};
   bool has_target_humidity{false};
   float target_humidity{0.0f};
 #ifdef HAS_PROTO_MESSAGE_DUMP
@@ -1695,12 +1685,11 @@ class SelectStateResponse final : public StateResponseProtoMessage {
 class SelectCommandRequest final : public CommandProtoMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 54;
-  static constexpr uint8_t ESTIMATED_SIZE = 28;
+  static constexpr uint8_t ESTIMATED_SIZE = 18;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "select_command_request"; }
 #endif
-  const uint8_t *state{nullptr};
-  uint16_t state_len{0};
+  StringRef state{};
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif
@@ -1719,7 +1708,7 @@ class ListEntitiesSirenResponse final : public InfoResponseProtoMessage {
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "list_entities_siren_response"; }
 #endif
-  std::vector<std::string> tones{};
+  const FixedVector<const char *> *tones{};
   bool supports_duration{false};
   bool supports_volume{false};
   void encode(ProtoWriteBuffer buffer) const override;
@@ -1756,7 +1745,7 @@ class SirenCommandRequest final : public CommandProtoMessage {
   bool has_state{false};
   bool state{false};
   bool has_tone{false};
-  std::string tone{};
+  StringRef tone{};
   bool has_duration{false};
   uint32_t duration{0};
   bool has_volume{false};
@@ -1817,7 +1806,7 @@ class LockCommandRequest final : public CommandProtoMessage {
 #endif
   enums::LockCommand command{};
   bool has_code{false};
-  std::string code{};
+  StringRef code{};
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif
@@ -1927,7 +1916,7 @@ class MediaPlayerCommandRequest final : public CommandProtoMessage {
   bool has_volume{false};
   float volume{0.0f};
   bool has_media_url{false};
-  std::string media_url{};
+  StringRef media_url{};
   bool has_announcement{false};
   bool announcement{false};
 #ifdef HAS_PROTO_MESSAGE_DUMP
@@ -2157,7 +2146,7 @@ class BluetoothGATTReadResponse final : public ProtoMessage {
 class BluetoothGATTWriteRequest final : public ProtoDecodableMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 75;
-  static constexpr uint8_t ESTIMATED_SIZE = 29;
+  static constexpr uint8_t ESTIMATED_SIZE = 19;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "bluetooth_gatt_write_request"; }
 #endif
@@ -2193,7 +2182,7 @@ class BluetoothGATTReadDescriptorRequest final : public ProtoDecodableMessage {
 class BluetoothGATTWriteDescriptorRequest final : public ProtoDecodableMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 77;
-  static constexpr uint8_t ESTIMATED_SIZE = 27;
+  static constexpr uint8_t ESTIMATED_SIZE = 17;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "bluetooth_gatt_write_descriptor_request"; }
 #endif
@@ -2503,8 +2492,8 @@ class VoiceAssistantResponse final : public ProtoDecodableMessage {
 };
 class VoiceAssistantEventData final : public ProtoDecodableMessage {
  public:
-  std::string name{};
-  std::string value{};
+  StringRef name{};
+  StringRef value{};
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif
@@ -2532,17 +2521,12 @@ class VoiceAssistantEventResponse final : public ProtoDecodableMessage {
 class VoiceAssistantAudio final : public ProtoDecodableMessage {
  public:
   static constexpr uint8_t MESSAGE_TYPE = 106;
-  static constexpr uint8_t ESTIMATED_SIZE = 11;
+  static constexpr uint8_t ESTIMATED_SIZE = 21;
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "voice_assistant_audio"; }
 #endif
-  std::string data{};
-  const uint8_t *data_ptr_{nullptr};
-  size_t data_len_{0};
-  void set_data(const uint8_t *data, size_t len) {
-    this->data_ptr_ = data;
-    this->data_len_ = len;
-  }
+  const uint8_t *data{nullptr};
+  uint16_t data_len{0};
   bool end{false};
   void encode(ProtoWriteBuffer buffer) const override;
   void calculate_size(ProtoSize &size) const override;
@@ -2562,8 +2546,8 @@ class VoiceAssistantTimerEventResponse final : public ProtoDecodableMessage {
   const char *message_name() const override { return "voice_assistant_timer_event_response"; }
 #endif
   enums::VoiceAssistantTimerEvent event_type{};
-  std::string timer_id{};
-  std::string name{};
+  StringRef timer_id{};
+  StringRef name{};
   uint32_t total_seconds{0};
   uint32_t seconds_left{0};
   bool is_active{false};
@@ -2582,9 +2566,9 @@ class VoiceAssistantAnnounceRequest final : public ProtoDecodableMessage {
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "voice_assistant_announce_request"; }
 #endif
-  std::string media_id{};
-  std::string text{};
-  std::string preannounce_media_id{};
+  StringRef media_id{};
+  StringRef text{};
+  StringRef preannounce_media_id{};
   bool start_conversation{false};
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
@@ -2627,13 +2611,13 @@ class VoiceAssistantWakeWord final : public ProtoMessage {
 };
 class VoiceAssistantExternalWakeWord final : public ProtoDecodableMessage {
  public:
-  std::string id{};
-  std::string wake_word{};
+  StringRef id{};
+  StringRef wake_word{};
   std::vector<std::string> trained_languages{};
-  std::string model_type{};
+  StringRef model_type{};
   uint32_t model_size{0};
-  std::string model_hash{};
-  std::string url{};
+  StringRef model_hash{};
+  StringRef url{};
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif
@@ -2734,7 +2718,7 @@ class AlarmControlPanelCommandRequest final : public CommandProtoMessage {
   const char *message_name() const override { return "alarm_control_panel_command_request"; }
 #endif
   enums::AlarmControlPanelStateCommand command{};
-  std::string code{};
+  StringRef code{};
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif
@@ -2791,7 +2775,7 @@ class TextCommandRequest final : public CommandProtoMessage {
 #ifdef HAS_PROTO_MESSAGE_DUMP
   const char *message_name() const override { return "text_command_request"; }
 #endif
-  std::string state{};
+  StringRef state{};
 #ifdef HAS_PROTO_MESSAGE_DUMP
   void dump_to(std::string &out) const override;
 #endif

esphome/components/api/api_pb2_dump.cpp

@@ -736,7 +736,7 @@ template<> const char *proto_enum_to_string<enums::ZWaveProxyRequestType>(enums:
 void HelloRequest::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "HelloRequest");
   out.append("  client_info: ");
-  out.append(format_hex_pretty(this->client_info, this->client_info_len));
+  out.append("'").append(this->client_info.c_str(), this->client_info.size()).append("'");
   out.append("\n");
   dump_field(out, "api_version_major", this->api_version_major);
   dump_field(out, "api_version_minor", this->api_version_minor);
@@ -752,7 +752,7 @@ void HelloResponse::dump_to(std::string &out) const {
 void AuthenticationRequest::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "AuthenticationRequest");
   out.append("  password: ");
-  out.append(format_hex_pretty(this->password, this->password_len));
+  out.append("'").append(this->password.c_str(), this->password.size()).append("'");
   out.append("\n");
 }
 void AuthenticationResponse::dump_to(std::string &out) const {
@@ -965,7 +965,7 @@ void FanCommandRequest::dump_to(std::string &out) const {
   dump_field(out, "speed_level", this->speed_level);
   dump_field(out, "has_preset_mode", this->has_preset_mode);
   out.append("  preset_mode: ");
-  out.append(format_hex_pretty(this->preset_mode, this->preset_mode_len));
+  out.append("'").append(this->preset_mode.c_str(), this->preset_mode.size()).append("'");
   out.append("\n");
 #ifdef USE_DEVICES
   dump_field(out, "device_id", this->device_id);
@@ -1043,7 +1043,7 @@ void LightCommandRequest::dump_to(std::string &out) const {
   dump_field(out, "flash_length", this->flash_length);
   dump_field(out, "has_effect", this->has_effect);
   out.append("  effect: ");
-  out.append(format_hex_pretty(this->effect, this->effect_len));
+  out.append("'").append(this->effect.c_str(), this->effect.size()).append("'");
   out.append("\n");
 #ifdef USE_DEVICES
   dump_field(out, "device_id", this->device_id);
@@ -1205,7 +1205,9 @@ void HomeassistantActionResponse::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "HomeassistantActionResponse");
   dump_field(out, "call_id", this->call_id);
   dump_field(out, "success", this->success);
-  dump_field(out, "error_message", this->error_message);
+  out.append("  error_message: ");
+  out.append("'").append(this->error_message.c_str(), this->error_message.size()).append("'");
+  out.append("\n");
 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
   out.append("  response_data: ");
   out.append(format_hex_pretty(this->response_data, this->response_data_len));
@@ -1226,13 +1228,13 @@ void SubscribeHomeAssistantStateResponse::dump_to(std::string &out) const {
 void HomeAssistantStateResponse::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "HomeAssistantStateResponse");
   out.append("  entity_id: ");
-  out.append(format_hex_pretty(this->entity_id, this->entity_id_len));
+  out.append("'").append(this->entity_id.c_str(), this->entity_id.size()).append("'");
   out.append("\n");
   out.append("  state: ");
-  out.append(format_hex_pretty(this->state, this->state_len));
+  out.append("'").append(this->state.c_str(), this->state.size()).append("'");
   out.append("\n");
   out.append("  attribute: ");
-  out.append(format_hex_pretty(this->attribute, this->attribute_len));
+  out.append("'").append(this->attribute.c_str(), this->attribute.size()).append("'");
   out.append("\n");
 }
 #endif
@@ -1241,7 +1243,7 @@ void GetTimeResponse::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "GetTimeResponse");
   dump_field(out, "epoch_seconds", this->epoch_seconds);
   out.append("  timezone: ");
-  out.append(format_hex_pretty(this->timezone, this->timezone_len));
+  out.append("'").append(this->timezone.c_str(), this->timezone.size()).append("'");
   out.append("\n");
 }
 #ifdef USE_API_USER_DEFINED_ACTIONS
@@ -1266,7 +1268,9 @@ void ExecuteServiceArgument::dump_to(std::string &out) const {
   dump_field(out, "bool_", this->bool_);
   dump_field(out, "legacy_int", this->legacy_int);
   dump_field(out, "float_", this->float_);
-  dump_field(out, "string_", this->string_);
+  out.append("  string_: ");
+  out.append("'").append(this->string_.c_str(), this->string_.size()).append("'");
+  out.append("\n");
   dump_field(out, "int_", this->int_);
   for (const auto it : this->bool_array) {
     dump_field(out, "bool_array", static_cast<bool>(it), 4);
@@ -1424,13 +1428,13 @@ void ClimateCommandRequest::dump_to(std::string &out) const {
   dump_field(out, "swing_mode", static_cast<enums::ClimateSwingMode>(this->swing_mode));
   dump_field(out, "has_custom_fan_mode", this->has_custom_fan_mode);
   out.append("  custom_fan_mode: ");
-  out.append(format_hex_pretty(this->custom_fan_mode, this->custom_fan_mode_len));
+  out.append("'").append(this->custom_fan_mode.c_str(), this->custom_fan_mode.size()).append("'");
   out.append("\n");
   dump_field(out, "has_preset", this->has_preset);
   dump_field(out, "preset", static_cast<enums::ClimatePreset>(this->preset));
   dump_field(out, "has_custom_preset", this->has_custom_preset);
   out.append("  custom_preset: ");
-  out.append(format_hex_pretty(this->custom_preset, this->custom_preset_len));
+  out.append("'").append(this->custom_preset.c_str(), this->custom_preset.size()).append("'");
   out.append("\n");
   dump_field(out, "has_target_humidity", this->has_target_humidity);
   dump_field(out, "target_humidity", this->target_humidity);
@@ -1558,7 +1562,7 @@ void SelectCommandRequest::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "SelectCommandRequest");
   dump_field(out, "key", this->key);
   out.append("  state: ");
-  out.append(format_hex_pretty(this->state, this->state_len));
+  out.append("'").append(this->state.c_str(), this->state.size()).append("'");
   out.append("\n");
 #ifdef USE_DEVICES
   dump_field(out, "device_id", this->device_id);
@@ -1575,7 +1579,7 @@ void ListEntitiesSirenResponse::dump_to(std::string &out) const {
   dump_field(out, "icon", this->icon_ref_);
 #endif
   dump_field(out, "disabled_by_default", this->disabled_by_default);
-  for (const auto &it : this->tones) {
+  for (const auto &it : *this->tones) {
     dump_field(out, "tones", it, 4);
   }
   dump_field(out, "supports_duration", this->supports_duration);
@@ -1599,7 +1603,9 @@ void SirenCommandRequest::dump_to(std::string &out) const {
   dump_field(out, "has_state", this->has_state);
   dump_field(out, "state", this->state);
   dump_field(out, "has_tone", this->has_tone);
-  dump_field(out, "tone", this->tone);
+  out.append("  tone: ");
+  out.append("'").append(this->tone.c_str(), this->tone.size()).append("'");
+  out.append("\n");
   dump_field(out, "has_duration", this->has_duration);
   dump_field(out, "duration", this->duration);
   dump_field(out, "has_volume", this->has_volume);
@@ -1641,7 +1647,9 @@ void LockCommandRequest::dump_to(std::string &out) const {
   dump_field(out, "key", this->key);
   dump_field(out, "command", static_cast<enums::LockCommand>(this->command));
   dump_field(out, "has_code", this->has_code);
-  dump_field(out, "code", this->code);
+  out.append("  code: ");
+  out.append("'").append(this->code.c_str(), this->code.size()).append("'");
+  out.append("\n");
 #ifdef USE_DEVICES
   dump_field(out, "device_id", this->device_id);
 #endif
@@ -1719,7 +1727,9 @@ void MediaPlayerCommandRequest::dump_to(std::string &out) const {
   dump_field(out, "has_volume", this->has_volume);
   dump_field(out, "volume", this->volume);
   dump_field(out, "has_media_url", this->has_media_url);
-  dump_field(out, "media_url", this->media_url);
+  out.append("  media_url: ");
+  out.append("'").append(this->media_url.c_str(), this->media_url.size()).append("'");
+  out.append("\n");
   dump_field(out, "has_announcement", this->has_announcement);
   dump_field(out, "announcement", this->announcement);
 #ifdef USE_DEVICES
@@ -1949,8 +1959,12 @@ void VoiceAssistantResponse::dump_to(std::string &out) const {
 }
 void VoiceAssistantEventData::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "VoiceAssistantEventData");
-  dump_field(out, "name", this->name);
-  dump_field(out, "value", this->value);
+  out.append("  name: ");
+  out.append("'").append(this->name.c_str(), this->name.size()).append("'");
+  out.append("\n");
+  out.append("  value: ");
+  out.append("'").append(this->value.c_str(), this->value.size()).append("'");
+  out.append("\n");
 }
 void VoiceAssistantEventResponse::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "VoiceAssistantEventResponse");
@@ -1964,28 +1978,34 @@ void VoiceAssistantEventResponse::dump_to(std::string &out) const {
 void VoiceAssistantAudio::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "VoiceAssistantAudio");
   out.append("  data: ");
-  if (this->data_ptr_ != nullptr) {
-    out.append(format_hex_pretty(this->data_ptr_, this->data_len_));
-  } else {
-    out.append(format_hex_pretty(reinterpret_cast<const uint8_t *>(this->data.data()), this->data.size()));
-  }
+  out.append(format_hex_pretty(this->data, this->data_len));
   out.append("\n");
   dump_field(out, "end", this->end);
 }
 void VoiceAssistantTimerEventResponse::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "VoiceAssistantTimerEventResponse");
   dump_field(out, "event_type", static_cast<enums::VoiceAssistantTimerEvent>(this->event_type));
-  dump_field(out, "timer_id", this->timer_id);
-  dump_field(out, "name", this->name);
+  out.append("  timer_id: ");
+  out.append("'").append(this->timer_id.c_str(), this->timer_id.size()).append("'");
+  out.append("\n");
+  out.append("  name: ");
+  out.append("'").append(this->name.c_str(), this->name.size()).append("'");
+  out.append("\n");
   dump_field(out, "total_seconds", this->total_seconds);
   dump_field(out, "seconds_left", this->seconds_left);
   dump_field(out, "is_active", this->is_active);
 }
 void VoiceAssistantAnnounceRequest::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "VoiceAssistantAnnounceRequest");
-  dump_field(out, "media_id", this->media_id);
-  dump_field(out, "text", this->text);
-  dump_field(out, "preannounce_media_id", this->preannounce_media_id);
+  out.append("  media_id: ");
+  out.append("'").append(this->media_id.c_str(), this->media_id.size()).append("'");
+  out.append("\n");
+  out.append("  text: ");
+  out.append("'").append(this->text.c_str(), this->text.size()).append("'");
+  out.append("\n");
+  out.append("  preannounce_media_id: ");
+  out.append("'").append(this->preannounce_media_id.c_str(), this->preannounce_media_id.size()).append("'");
+  out.append("\n");
   dump_field(out, "start_conversation", this->start_conversation);
 }
 void VoiceAssistantAnnounceFinished::dump_to(std::string &out) const { dump_field(out, "success", this->success); }
@@ -1999,15 +2019,25 @@ void VoiceAssistantWakeWord::dump_to(std::string &out) const {
 }
 void VoiceAssistantExternalWakeWord::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "VoiceAssistantExternalWakeWord");
-  dump_field(out, "id", this->id);
-  dump_field(out, "wake_word", this->wake_word);
+  out.append("  id: ");
+  out.append("'").append(this->id.c_str(), this->id.size()).append("'");
+  out.append("\n");
+  out.append("  wake_word: ");
+  out.append("'").append(this->wake_word.c_str(), this->wake_word.size()).append("'");
+  out.append("\n");
   for (const auto &it : this->trained_languages) {
     dump_field(out, "trained_languages", it, 4);
   }
-  dump_field(out, "model_type", this->model_type);
+  out.append("  model_type: ");
+  out.append("'").append(this->model_type.c_str(), this->model_type.size()).append("'");
+  out.append("\n");
   dump_field(out, "model_size", this->model_size);
-  dump_field(out, "model_hash", this->model_hash);
-  dump_field(out, "url", this->url);
+  out.append("  model_hash: ");
+  out.append("'").append(this->model_hash.c_str(), this->model_hash.size()).append("'");
+  out.append("\n");
+  out.append("  url: ");
+  out.append("'").append(this->url.c_str(), this->url.size()).append("'");
+  out.append("\n");
 }
 void VoiceAssistantConfigurationRequest::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "VoiceAssistantConfigurationRequest");
@@ -2066,7 +2096,9 @@ void AlarmControlPanelCommandRequest::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "AlarmControlPanelCommandRequest");
   dump_field(out, "key", this->key);
   dump_field(out, "command", static_cast<enums::AlarmControlPanelStateCommand>(this->command));
-  dump_field(out, "code", this->code);
+  out.append("  code: ");
+  out.append("'").append(this->code.c_str(), this->code.size()).append("'");
+  out.append("\n");
 #ifdef USE_DEVICES
   dump_field(out, "device_id", this->device_id);
 #endif
@@ -2103,7 +2135,9 @@ void TextStateResponse::dump_to(std::string &out) const {
 void TextCommandRequest::dump_to(std::string &out) const {
   MessageDumpHelper helper(out, "TextCommandRequest");
   dump_field(out, "key", this->key);
-  dump_field(out, "state", this->state);
+  out.append("  state: ");
+  out.append("'").append(this->state.c_str(), this->state.size()).append("'");
+  out.append("\n");
 #ifdef USE_DEVICES
   dump_field(out, "device_id", this->device_id);
 #endif

esphome/components/api/api_server.cpp

@@ -187,13 +187,14 @@ void APIServer::loop() {
 
     // Rare case: handle disconnection
 #ifdef USE_API_CLIENT_DISCONNECTED_TRIGGER
-    // Trigger expects std::string, get fresh peername from socket
-    this->client_disconnected_trigger_->trigger(client->client_info_.name, client->get_peername());
+    char peername_buf[socket::PEERNAME_MAX_LEN];
+    client->get_peername_to(peername_buf);
+    this->client_disconnected_trigger_->trigger(std::string(client->get_name()), std::string(peername_buf));
 #endif
 #ifdef USE_API_USER_DEFINED_ACTION_RESPONSES
     this->unregister_active_action_calls_for_connection(client.get());
 #endif
-    ESP_LOGV(TAG, "Remove connection %s", client->client_info_.name.c_str());
+    ESP_LOGV(TAG, "Remove connection %s", client->get_name());
 
     // Swap with the last element and pop (avoids expensive vector shifts)
     if (client_index < this->clients_.size() - 1) {
@@ -397,7 +398,7 @@ void APIServer::register_action_response_callback(uint32_t call_id, ActionRespon
   this->action_response_callbacks_.push_back({call_id, std::move(callback)});
 }
 
-void APIServer::handle_action_response(uint32_t call_id, bool success, const std::string &error_message) {
+void APIServer::handle_action_response(uint32_t call_id, bool success, StringRef error_message) {
   for (auto it = this->action_response_callbacks_.begin(); it != this->action_response_callbacks_.end(); ++it) {
     if (it->call_id == call_id) {
       auto callback = std::move(it->callback);
@@ -409,7 +410,7 @@ void APIServer::handle_action_response(uint32_t call_id, bool success, const std
   }
 }
 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
-void APIServer::handle_action_response(uint32_t call_id, bool success, const std::string &error_message,
+void APIServer::handle_action_response(uint32_t call_id, bool success, StringRef error_message,
                                        const uint8_t *response_data, size_t response_data_len) {
   for (auto it = this->action_response_callbacks_.begin(); it != this->action_response_callbacks_.end(); ++it) {
     if (it->call_id == call_id) {
@@ -427,8 +428,8 @@ void APIServer::handle_action_response(uint32_t call_id, bool success, const std
 
 #ifdef USE_API_HOMEASSISTANT_STATES
 // Helper to add subscription (reduces duplication)
-void APIServer::add_state_subscription_(const char *entity_id, const char *attribute,
-                                        std::function<void(const std::string &)> f, bool once) {
+void APIServer::add_state_subscription_(const char *entity_id, const char *attribute, std::function<void(StringRef)> f,
+                                        bool once) {
   this->state_subs_.push_back(HomeAssistantStateSubscription{
       .entity_id = entity_id, .attribute = attribute, .callback = std::move(f), .once = once,
       // entity_id_dynamic_storage and attribute_dynamic_storage remain nullptr (no heap allocation)
@@ -437,7 +438,7 @@ void APIServer::add_state_subscription_(const char *entity_id, const char *attri
 
 // Helper to add subscription with heap-allocated strings (reduces duplication)
 void APIServer::add_state_subscription_(std::string entity_id, optional<std::string> attribute,
-                                        std::function<void(const std::string &)> f, bool once) {
+                                        std::function<void(StringRef)> f, bool once) {
   HomeAssistantStateSubscription sub;
   // Allocate heap storage for the strings
   sub.entity_id_dynamic_storage = std::make_unique<std::string>(std::move(entity_id));
@@ -457,16 +458,36 @@ void APIServer::add_state_subscription_(std::string entity_id, optional<std::str
 
 // New const char* overload (for internal components - zero allocation)
 void APIServer::subscribe_home_assistant_state(const char *entity_id, const char *attribute,
-                                               std::function<void(const std::string &)> f) {
+                                               std::function<void(StringRef)> f) {
   this->add_state_subscription_(entity_id, attribute, std::move(f), false);
 }
 
 void APIServer::get_home_assistant_state(const char *entity_id, const char *attribute,
-                                         std::function<void(const std::string &)> f) {
+                                         std::function<void(StringRef)> f) {
   this->add_state_subscription_(entity_id, attribute, std::move(f), true);
 }
 
-// Existing std::string overload (for custom_api_device.h - heap allocation)
+// std::string overload with StringRef callback (zero-allocation callback)
+void APIServer::subscribe_home_assistant_state(std::string entity_id, optional<std::string> attribute,
+                                               std::function<void(StringRef)> f) {
+  this->add_state_subscription_(std::move(entity_id), std::move(attribute), std::move(f), false);
+}
+
+void APIServer::get_home_assistant_state(std::string entity_id, optional<std::string> attribute,
+                                         std::function<void(StringRef)> f) {
+  this->add_state_subscription_(std::move(entity_id), std::move(attribute), std::move(f), true);
+}
+
+// Legacy helper: wraps std::string callback and delegates to StringRef version
+void APIServer::add_state_subscription_(std::string entity_id, optional<std::string> attribute,
+                                        std::function<void(const std::string &)> f, bool once) {
+  // Wrap callback to convert StringRef -> std::string, then delegate
+  this->add_state_subscription_(std::move(entity_id), std::move(attribute),
+                                std::function<void(StringRef)>([f = std::move(f)](StringRef state) { f(state.str()); }),
+                                once);
+}
+
+// Legacy std::string overload (for custom_api_device.h - converts StringRef to std::string)
 void APIServer::subscribe_home_assistant_state(std::string entity_id, optional<std::string> attribute,
                                                std::function<void(const std::string &)> f) {
   this->add_state_subscription_(std::move(entity_id), std::move(attribute), std::move(f), false);
@@ -681,7 +702,7 @@ void APIServer::unregister_active_action_calls_for_connection(APIConnection *con
   }
 }
 
-void APIServer::send_action_response(uint32_t action_call_id, bool success, const std::string &error_message) {
+void APIServer::send_action_response(uint32_t action_call_id, bool success, StringRef error_message) {
   for (auto &call : this->active_action_calls_) {
     if (call.action_call_id == action_call_id) {
       call.connection->send_execute_service_response(call.client_call_id, success, error_message);
@@ -691,7 +712,7 @@ void APIServer::send_action_response(uint32_t action_call_id, bool success, cons
   ESP_LOGW(TAG, "Cannot send response: no active call found for action_call_id %u", action_call_id);
 }
 #ifdef USE_API_USER_DEFINED_ACTION_RESPONSES_JSON
-void APIServer::send_action_response(uint32_t action_call_id, bool success, const std::string &error_message,
+void APIServer::send_action_response(uint32_t action_call_id, bool success, StringRef error_message,
                                      const uint8_t *response_data, size_t response_data_len) {
   for (auto &call : this->active_action_calls_) {
     if (call.action_call_id == action_call_id) {

esphome/components/api/api_server.h

@@ -10,6 +10,7 @@
 #include "esphome/core/component.h"
 #include "esphome/core/controller.h"
 #include "esphome/core/log.h"
+#include "esphome/core/string_ref.h"
 #include "list_entities.h"
 #include "subscribe_state.h"
 #ifdef USE_LOGGER
@@ -143,10 +144,10 @@ class APIServer : public Component,
   // Action response handling
   using ActionResponseCallback = std::function<void(const class ActionResponse &)>;
   void register_action_response_callback(uint32_t call_id, ActionResponseCallback callback);
-  void handle_action_response(uint32_t call_id, bool success, const std::string &error_message);
+  void handle_action_response(uint32_t call_id, bool success, StringRef error_message);
 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
-  void handle_action_response(uint32_t call_id, bool success, const std::string &error_message,
-                              const uint8_t *response_data, size_t response_data_len);
+  void handle_action_response(uint32_t call_id, bool success, StringRef error_message, const uint8_t *response_data,
+                              size_t response_data_len);
 #endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
 #endif  // USE_API_HOMEASSISTANT_ACTION_RESPONSES
 #endif  // USE_API_HOMEASSISTANT_SERVICES
@@ -165,9 +166,9 @@ class APIServer : public Component,
   void unregister_active_action_call(uint32_t action_call_id);
   void unregister_active_action_calls_for_connection(APIConnection *conn);
   // Send response for a specific action call (uses action_call_id, sends client_call_id in response)
-  void send_action_response(uint32_t action_call_id, bool success, const std::string &error_message);
+  void send_action_response(uint32_t action_call_id, bool success, StringRef error_message);
 #ifdef USE_API_USER_DEFINED_ACTION_RESPONSES_JSON
-  void send_action_response(uint32_t action_call_id, bool success, const std::string &error_message,
+  void send_action_response(uint32_t action_call_id, bool success, StringRef error_message,
                             const uint8_t *response_data, size_t response_data_len);
 #endif  // USE_API_USER_DEFINED_ACTION_RESPONSES_JSON
 #endif  // USE_API_USER_DEFINED_ACTION_RESPONSES
@@ -195,7 +196,7 @@ class APIServer : public Component,
   struct HomeAssistantStateSubscription {
     const char *entity_id;  // Pointer to flash (internal) or heap (external)
     const char *attribute;  // Pointer to flash or nullptr (nullptr means no attribute)
-    std::function<void(const std::string &)> callback;
+    std::function<void(StringRef)> callback;
     bool once;
 
     // Dynamic storage for external components using std::string API (custom_api_device.h)
@@ -205,12 +206,16 @@ class APIServer : public Component,
   };
 
   // New const char* overload (for internal components - zero allocation)
-  void subscribe_home_assistant_state(const char *entity_id, const char *attribute,
-                                      std::function<void(const std::string &)> f);
-  void get_home_assistant_state(const char *entity_id, const char *attribute,
-                                std::function<void(const std::string &)> f);
+  void subscribe_home_assistant_state(const char *entity_id, const char *attribute, std::function<void(StringRef)> f);
+  void get_home_assistant_state(const char *entity_id, const char *attribute, std::function<void(StringRef)> f);
 
-  // Existing std::string overload (for custom_api_device.h - heap allocation)
+  // std::string overload with StringRef callback (for custom_api_device.h with zero-allocation callback)
+  void subscribe_home_assistant_state(std::string entity_id, optional<std::string> attribute,
+                                      std::function<void(StringRef)> f);
+  void get_home_assistant_state(std::string entity_id, optional<std::string> attribute,
+                                std::function<void(StringRef)> f);
+
+  // Legacy std::string overload (for custom_api_device.h - converts StringRef to std::string for callback)
   void subscribe_home_assistant_state(std::string entity_id, optional<std::string> attribute,
                                       std::function<void(const std::string &)> f);
   void get_home_assistant_state(std::string entity_id, optional<std::string> attribute,
@@ -238,8 +243,11 @@ class APIServer : public Component,
 #endif  // USE_API_NOISE
 #ifdef USE_API_HOMEASSISTANT_STATES
   // Helper methods to reduce code duplication
-  void add_state_subscription_(const char *entity_id, const char *attribute, std::function<void(const std::string &)> f,
+  void add_state_subscription_(const char *entity_id, const char *attribute, std::function<void(StringRef)> f,
                                bool once);
+  void add_state_subscription_(std::string entity_id, optional<std::string> attribute, std::function<void(StringRef)> f,
+                               bool once);
+  // Legacy helper: wraps std::string callback and delegates to StringRef version
   void add_state_subscription_(std::string entity_id, optional<std::string> attribute,
                                std::function<void(const std::string &)> f, bool once);
 #endif  // USE_API_HOMEASSISTANT_STATES

esphome/components/api/custom_api_device.h

@@ -122,21 +122,36 @@ class CustomAPIDevice {
    *   subscribe_homeassistant_state(&CustomNativeAPI::on_state_changed, "climate.kitchen", "current_temperature");
    * }
    *
-   * void on_state_changed(const std::string &state) {
-   *   // State of sensor.weather_forecast is `state`
+   * void on_state_changed(StringRef state) {
+   *   // State of climate.kitchen current_temperature is `state`
+   *   // Use state.c_str() for C string, state.str() for std::string
    * }
    * ```
    *
    * @tparam T The class type creating the service, automatically deduced from the function pointer.
-   * @param callback The member function to call when the entity state changes.
+   * @param callback The member function to call when the entity state changes (zero-allocation).
    * @param entity_id The entity_id to track.
    * @param attribute The entity state attribute to track.
    */
   template<typename T>
-  void subscribe_homeassistant_state(void (T::*callback)(const std::string &), const std::string &entity_id,
+  void subscribe_homeassistant_state(void (T::*callback)(StringRef), const std::string &entity_id,
                                      const std::string &attribute = "") {
     auto f = std::bind(callback, (T *) this, std::placeholders::_1);
-    global_api_server->subscribe_home_assistant_state(entity_id, optional<std::string>(attribute), f);
+    global_api_server->subscribe_home_assistant_state(entity_id, optional<std::string>(attribute), std::move(f));
+  }
+
+  /** Subscribe to the state (or attribute state) of an entity from Home Assistant (legacy std::string version).
+   *
+   * @deprecated Use the StringRef overload for zero-allocation callbacks. Will be removed in 2027.1.0.
+   */
+  template<typename T>
+  ESPDEPRECATED("Use void callback(StringRef) instead. Will be removed in 2027.1.0.", "2026.1.0")
+  void subscribe_homeassistant_state(void (T::*callback)(std::string), const std::string &entity_id,
+                                     const std::string &attribute = "") {
+    auto f = std::bind(callback, (T *) this, std::placeholders::_1);
+    // Explicit type to disambiguate overload resolution
+    global_api_server->subscribe_home_assistant_state(entity_id, optional<std::string>(attribute),
+                                                      std::function<void(const std::string &)>(f));
   }
 
   /** Subscribe to the state (or attribute state) of an entity from Home Assistant.
@@ -148,25 +163,39 @@ class CustomAPIDevice {
    *   subscribe_homeassistant_state(&CustomNativeAPI::on_state_changed, "sensor.weather_forecast");
    * }
    *
-   * void on_state_changed(const std::string &entity_id, const std::string &state) {
+   * void on_state_changed(const std::string &entity_id, StringRef state) {
    *   // State of `entity_id` is `state`
    * }
    * ```
    *
    * @tparam T The class type creating the service, automatically deduced from the function pointer.
-   * @param callback The member function to call when the entity state changes.
+   * @param callback The member function to call when the entity state changes (zero-allocation for state).
    * @param entity_id The entity_id to track.
    * @param attribute The entity state attribute to track.
    */
   template<typename T>
-  void subscribe_homeassistant_state(void (T::*callback)(const std::string &, const std::string &),
-                                     const std::string &entity_id, const std::string &attribute = "") {
+  void subscribe_homeassistant_state(void (T::*callback)(const std::string &, StringRef), const std::string &entity_id,
+                                     const std::string &attribute = "") {
     auto f = std::bind(callback, (T *) this, entity_id, std::placeholders::_1);
-    global_api_server->subscribe_home_assistant_state(entity_id, optional<std::string>(attribute), f);
+    global_api_server->subscribe_home_assistant_state(entity_id, optional<std::string>(attribute), std::move(f));
+  }
+
+  /** Subscribe to the state (or attribute state) of an entity from Home Assistant (legacy std::string version).
+   *
+   * @deprecated Use the StringRef overload for zero-allocation callbacks. Will be removed in 2027.1.0.
+   */
+  template<typename T>
+  ESPDEPRECATED("Use void callback(const std::string &, StringRef) instead. Will be removed in 2027.1.0.", "2026.1.0")
+  void subscribe_homeassistant_state(void (T::*callback)(std::string, std::string), const std::string &entity_id,
+                                     const std::string &attribute = "") {
+    auto f = std::bind(callback, (T *) this, entity_id, std::placeholders::_1);
+    // Explicit type to disambiguate overload resolution
+    global_api_server->subscribe_home_assistant_state(entity_id, optional<std::string>(attribute),
+                                                      std::function<void(const std::string &)>(f));
   }
 #else
   template<typename T>
-  void subscribe_homeassistant_state(void (T::*callback)(const std::string &), const std::string &entity_id,
+  void subscribe_homeassistant_state(void (T::*callback)(StringRef), const std::string &entity_id,
                                      const std::string &attribute = "") {
     static_assert(sizeof(T) == 0,
                   "subscribe_homeassistant_state() requires 'homeassistant_states: true' in the 'api:' section "
@@ -174,8 +203,24 @@ class CustomAPIDevice {
   }
 
   template<typename T>
-  void subscribe_homeassistant_state(void (T::*callback)(const std::string &, const std::string &),
-                                     const std::string &entity_id, const std::string &attribute = "") {
+  void subscribe_homeassistant_state(void (T::*callback)(std::string), const std::string &entity_id,
+                                     const std::string &attribute = "") {
+    static_assert(sizeof(T) == 0,
+                  "subscribe_homeassistant_state() requires 'homeassistant_states: true' in the 'api:' section "
+                  "of your YAML configuration");
+  }
+
+  template<typename T>
+  void subscribe_homeassistant_state(void (T::*callback)(const std::string &, StringRef), const std::string &entity_id,
+                                     const std::string &attribute = "") {
+    static_assert(sizeof(T) == 0,
+                  "subscribe_homeassistant_state() requires 'homeassistant_states: true' in the 'api:' section "
+                  "of your YAML configuration");
+  }
+
+  template<typename T>
+  void subscribe_homeassistant_state(void (T::*callback)(std::string, std::string), const std::string &entity_id,
+                                     const std::string &attribute = "") {
     static_assert(sizeof(T) == 0,
                   "subscribe_homeassistant_state() requires 'homeassistant_states: true' in the 'api:' section "
                   "of your YAML configuration");

esphome/components/api/homeassistant_service.h

@@ -67,10 +67,10 @@ template<typename... Ts> class TemplatableKeyValuePair {
 // the callback is invoked synchronously while the message is on the stack).
 class ActionResponse {
  public:
-  ActionResponse(bool success, const std::string &error_message) : success_(success), error_message_(error_message) {}
+  ActionResponse(bool success, StringRef error_message) : success_(success), error_message_(error_message) {}
 
 #ifdef USE_API_HOMEASSISTANT_ACTION_RESPONSES_JSON
-  ActionResponse(bool success, const std::string &error_message, const uint8_t *data, size_t data_len)
+  ActionResponse(bool success, StringRef error_message, const uint8_t *data, size_t data_len)
       : success_(success), error_message_(error_message) {
     if (data == nullptr || data_len == 0)
       return;

esphome/components/audio/audio_reader.cpp

@@ -1,6 +1,6 @@
 #include "audio_reader.h"
 
-#ifdef USE_ESP_IDF
+#ifdef USE_ESP32
 
 #include "esphome/core/defines.h"
 #include "esphome/core/hal.h"

esphome/components/audio/audio_reader.h

@@ -1,6 +1,6 @@
 #pragma once
 
-#ifdef USE_ESP_IDF
+#ifdef USE_ESP32
 
 #include "audio.h"
 #include "audio_transfer_buffer.h"

esphome/components/ble_client/automation.h

@@ -7,8 +7,12 @@
 
 #include "esphome/core/automation.h"
 #include "esphome/components/ble_client/ble_client.h"
+#include "esphome/core/helpers.h"
 #include "esphome/core/log.h"
 
+// Maximum bytes to log in hex format for BLE writes (many logging buffers are 256 chars)
+static constexpr size_t BLE_WRITE_MAX_LOG_BYTES = 64;
+
 namespace esphome::ble_client {
 
 // placeholder class for static TAG .
@@ -151,7 +155,10 @@ template<typename... Ts> class BLEClientWriteAction : public Action<Ts...>, publ
       esph_log_w(Automation::TAG, "Cannot write to BLE characteristic - not connected");
       return false;
     }
-    esph_log_vv(Automation::TAG, "Will write %d bytes: %s", len, format_hex_pretty(data, len).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERY_VERBOSE
+    char hex_buf[format_hex_pretty_size(BLE_WRITE_MAX_LOG_BYTES)];
+    esph_log_vv(Automation::TAG, "Will write %d bytes: %s", len, format_hex_pretty_to(hex_buf, data, len));
+#endif
     esp_err_t err =
         esp_ble_gattc_write_char(this->parent()->get_gattc_if(), this->parent()->get_conn_id(), this->char_handle_, len,
                                  const_cast<uint8_t *>(data), this->write_type_, ESP_GATT_AUTH_REQ_NONE);

esphome/components/bme68x_bsec2/sensor.py

@@ -50,6 +50,7 @@ TYPES = [
 
 CONFIG_SCHEMA = cv.Schema(
     {
+        cv.GenerateID(): cv.declare_id(cg.Component),
         cv.GenerateID(CONF_BME68X_BSEC2_ID): cv.use_id(BME68xBSEC2Component),
         cv.Optional(CONF_TEMPERATURE): sensor.sensor_schema(
             unit_of_measurement=UNIT_CELSIUS,

esphome/components/captive_portal/__init__.py

@@ -97,10 +97,6 @@ async def to_code(config):
     cg.add_define("USE_CAPTIVE_PORTAL")
 
     if CORE.using_arduino:
-        if CORE.is_esp32:
-            cg.add_library("ESP32 Async UDP", None)
-            cg.add_library("DNSServer", None)
-            cg.add_library("WiFi", None)
         if CORE.is_esp8266:
             cg.add_library("DNSServer", None)
         if CORE.is_libretiny:
@@ -110,6 +106,9 @@ async def to_code(config):
 # Only compile the ESP-IDF DNS server when using ESP-IDF framework
 FILTER_SOURCE_FILES = filter_source_files_from_platform(
     {
-        "dns_server_esp32_idf.cpp": {PlatformFramework.ESP32_IDF},
+        "dns_server_esp32_idf.cpp": {
+            PlatformFramework.ESP32_ARDUINO,
+            PlatformFramework.ESP32_IDF,
+        },
     }
 )

esphome/components/captive_portal/captive_portal.cpp

@@ -69,12 +69,11 @@ void CaptivePortal::start() {
 
   network::IPAddress ip = wifi::global_wifi_component->wifi_soft_ap_ip();
 
-#ifdef USE_ESP_IDF
+#if defined(USE_ESP32)
   // Create DNS server instance for ESP-IDF
   this->dns_server_ = make_unique<DNSServer>();
   this->dns_server_->start(ip);
-#endif
-#ifdef USE_ARDUINO
+#elif defined(USE_ARDUINO)
   this->dns_server_ = make_unique<DNSServer>();
   this->dns_server_->setErrorReplyCode(DNSReplyCode::NoError);
   this->dns_server_->start(53, ESPHOME_F("*"), ip);

esphome/components/captive_portal/captive_portal.h

@@ -2,11 +2,10 @@
 #include "esphome/core/defines.h"
 #ifdef USE_CAPTIVE_PORTAL
 #include <memory>
-#ifdef USE_ARDUINO
-#include <DNSServer.h>
-#endif
-#ifdef USE_ESP_IDF
+#if defined(USE_ESP32)
 #include "dns_server_esp32_idf.h"
+#elif defined(USE_ARDUINO)
+#include <DNSServer.h>
 #endif
 #include "esphome/core/component.h"
 #include "esphome/core/helpers.h"
@@ -23,15 +22,14 @@ class CaptivePortal : public AsyncWebHandler, public Component {
   void setup() override;
   void dump_config() override;
   void loop() override {
-#ifdef USE_ARDUINO
-    if (this->dns_server_ != nullptr) {
-      this->dns_server_->processNextRequest();
-    }
-#endif
-#ifdef USE_ESP_IDF
+#if defined(USE_ESP32)
     if (this->dns_server_ != nullptr) {
       this->dns_server_->process_next_request();
     }
+#elif defined(USE_ARDUINO)
+    if (this->dns_server_ != nullptr) {
+      this->dns_server_->processNextRequest();
+    }
 #endif
   }
   float get_setup_priority() const override;
@@ -64,7 +62,7 @@ class CaptivePortal : public AsyncWebHandler, public Component {
   web_server_base::WebServerBase *base_;
   bool initialized_{false};
   bool active_{false};
-#if defined(USE_ARDUINO) || defined(USE_ESP_IDF)
+#if defined(USE_ARDUINO) || defined(USE_ESP32)
   std::unique_ptr<DNSServer> dns_server_{nullptr};
 #endif
 };

esphome/components/captive_portal/dns_server_esp32_idf.cpp

@@ -1,5 +1,5 @@
 #include "dns_server_esp32_idf.h"
-#ifdef USE_ESP_IDF
+#ifdef USE_ESP32
 
 #include "esphome/core/log.h"
 #include "esphome/core/hal.h"
@@ -47,7 +47,10 @@ struct DNSAnswer {
 
 void DNSServer::start(const network::IPAddress &ip) {
   this->server_ip_ = ip;
-  ESP_LOGV(TAG, "Starting DNS server on %s", ip.str().c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  char ip_buf[network::IP_ADDRESS_BUFFER_SIZE];
+  ESP_LOGV(TAG, "Starting DNS server on %s", ip.str_to(ip_buf));
+#endif
 
   // Create loop-monitored UDP socket
   this->socket_ = socket::socket_ip_loop_monitored(SOCK_DGRAM, IPPROTO_UDP);
@@ -202,4 +205,4 @@ void DNSServer::process_next_request() {
 
 }  // namespace esphome::captive_portal
 
-#endif  // USE_ESP_IDF
+#endif  // USE_ESP32

esphome/components/captive_portal/dns_server_esp32_idf.h

@@ -1,5 +1,5 @@
 #pragma once
-#ifdef USE_ESP_IDF
+#ifdef USE_ESP32
 
 #include <memory>
 #include "esphome/core/helpers.h"
@@ -24,4 +24,4 @@ class DNSServer {
 
 }  // namespace esphome::captive_portal
 
-#endif  // USE_ESP_IDF
+#endif  // USE_ESP32

esphome/components/cc1101/cc1101.cpp

@@ -169,14 +169,16 @@ void CC1101Component::loop() {
   }
 
   // Read packet
-  uint8_t payload_length;
+  uint8_t payload_length, expected_rx;
   if (this->state_.LENGTH_CONFIG == static_cast<uint8_t>(LengthConfig::LENGTH_CONFIG_VARIABLE)) {
     this->read_(Register::FIFO, &payload_length, 1);
+    expected_rx = payload_length + 1;
   } else {
     payload_length = this->state_.PKTLEN;
+    expected_rx = payload_length;
   }
-  if (payload_length == 0 || payload_length > 64) {
-    ESP_LOGW(TAG, "Invalid payload length: %u", payload_length);
+  if (payload_length == 0 || payload_length > 64 || rx_bytes != expected_rx) {
+    ESP_LOGW(TAG, "Invalid packet: rx_bytes %u, payload_length %u", rx_bytes, payload_length);
     this->enter_idle_();
     this->strobe_(Command::FRX);
     this->strobe_(Command::RX);
@@ -186,13 +188,12 @@ void CC1101Component::loop() {
   this->packet_.resize(payload_length);
   this->read_(Register::FIFO, this->packet_.data(), payload_length);
 
-  // Read status and trigger
-  uint8_t status[2];
-  this->read_(Register::FIFO, status, 2);
-  int8_t rssi_raw = static_cast<int8_t>(status[0]);
-  float rssi = (rssi_raw * RSSI_STEP) - RSSI_OFFSET;
-  bool crc_ok = (status[1] & STATUS_CRC_OK_MASK) != 0;
-  uint8_t lqi = status[1] & STATUS_LQI_MASK;
+  // Read status from registers (more reliable than FIFO status bytes due to timing issues)
+  this->read_(Register::RSSI);
+  this->read_(Register::LQI);
+  float rssi = (this->state_.RSSI * RSSI_STEP) - RSSI_OFFSET;
+  bool crc_ok = (this->state_.LQI & STATUS_CRC_OK_MASK) != 0;
+  uint8_t lqi = this->state_.LQI & STATUS_LQI_MASK;
   if (this->state_.CRC_EN == 0 || crc_ok) {
     this->packet_trigger_->trigger(this->packet_, rssi, lqi);
   }
@@ -616,12 +617,15 @@ void CC1101Component::set_packet_mode(bool value) {
     this->state_.GDO0_CFG = 0x01;
     // Set max RX FIFO threshold to ensure we only trigger on end-of-packet
     this->state_.FIFO_THR = 15;
+    // Don't append status bytes to FIFO - we read from registers instead
+    this->state_.APPEND_STATUS = 0;
   } else {
     // Configure GDO0 for serial data (async serial mode)
     this->state_.GDO0_CFG = 0x0D;
   }
   if (this->initialized_) {
     this->write_(Register::PKTCTRL0);
+    this->write_(Register::PKTCTRL1);
     this->write_(Register::IOCFG0);
     this->write_(Register::FIFOTHR);
   }

esphome/components/ch422g/ch422g.cpp

@@ -128,7 +128,9 @@ void CH422GGPIOPin::pin_mode(gpio::Flags flags) { this->parent_->pin_mode(this->
 bool CH422GGPIOPin::digital_read() { return this->parent_->digital_read(this->pin_) ^ this->inverted_; }
 
 void CH422GGPIOPin::digital_write(bool value) { this->parent_->digital_write(this->pin_, value ^ this->inverted_); }
-std::string CH422GGPIOPin::dump_summary() const { return str_sprintf("EXIO%u via CH422G", pin_); }
+size_t CH422GGPIOPin::dump_summary(char *buffer, size_t len) const {
+  return snprintf(buffer, len, "EXIO%u via CH422G", this->pin_);
+}
 void CH422GGPIOPin::set_flags(gpio::Flags flags) {
   flags_ = flags;
   this->parent_->pin_mode(this->pin_, flags);

esphome/components/ch422g/ch422g.h

@@ -50,7 +50,7 @@ class CH422GGPIOPin : public GPIOPin {
   void pin_mode(gpio::Flags flags) override;
   bool digital_read() override;
   void digital_write(bool value) override;
-  std::string dump_summary() const override;
+  size_t dump_summary(char *buffer, size_t len) const override;
 
   void set_parent(CH422GComponent *parent) { parent_ = parent; }
   void set_pin(uint8_t pin) { pin_ = pin; }

esphome/components/climate/climate.cpp

@@ -369,7 +369,7 @@ optional<ClimateDeviceRestoreState> Climate::restore_state_() {
 }
 
 void Climate::save_state_() {
-#if (defined(USE_ESP_IDF) || (defined(USE_ESP8266) && USE_ARDUINO_VERSION_CODE >= VERSION_CODE(3, 0, 0))) && \
+#if (defined(USE_ESP32) || (defined(USE_ESP8266) && USE_ARDUINO_VERSION_CODE >= VERSION_CODE(3, 0, 0))) && \
     !defined(CLANG_TIDY)
 #pragma GCC diagnostic ignored "-Wclass-memaccess"
 #define TEMP_IGNORE_MEMACCESS

esphome/components/cse7766/cse7766.cpp

@@ -1,11 +1,13 @@
 #include "cse7766.h"
-#include "esphome/core/log.h"
 #include "esphome/core/application.h"
+#include "esphome/core/helpers.h"
+#include "esphome/core/log.h"
 
 namespace esphome {
 namespace cse7766 {
 
 static const char *const TAG = "cse7766";
+static constexpr size_t CSE7766_RAW_DATA_SIZE = 24;
 
 void CSE7766Component::loop() {
   const uint32_t now = App.get_loop_component_start_time();
@@ -70,8 +72,8 @@ bool CSE7766Component::check_byte_() {
 void CSE7766Component::parse_data_() {
 #if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERY_VERBOSE
   {
-    std::string s = format_hex_pretty(this->raw_data_, sizeof(this->raw_data_));
-    ESP_LOGVV(TAG, "Raw data: %s", s.c_str());
+    char hex_buf[format_hex_pretty_size(CSE7766_RAW_DATA_SIZE)];
+    ESP_LOGVV(TAG, "Raw data: %s", format_hex_pretty_to(hex_buf, this->raw_data_, sizeof(this->raw_data_)));
   }
 #endif
 

esphome/components/dallas_temp/dallas_temp.cpp

@@ -51,7 +51,7 @@ void DallasTemperatureSensor::update() {
     }
 
     float tempc = this->get_temp_c_();
-    ESP_LOGD(TAG, "'%s': Got Temperature=%.1f°C", this->get_name().c_str(), tempc);
+    ESP_LOGD(TAG, "'%s': Got Temperature=%f°C", this->get_name().c_str(), tempc);
     this->publish_state(tempc);
   });
 }

esphome/components/debug/debug_esp32.cpp

@@ -200,7 +200,7 @@ void DebugComponent::get_device_info_(std::string &device_info) {
 #ifdef USE_ARDUINO
   ESP_LOGD(TAG, "Framework: Arduino");
   device_info += "Arduino";
-#elif defined(USE_ESP_IDF)
+#elif defined(USE_ESP32)
   ESP_LOGD(TAG, "Framework: ESP-IDF");
   device_info += "ESP-IDF";
 #else

esphome/components/ee895/ee895.cpp

@@ -7,6 +7,9 @@ namespace ee895 {
 
 static const char *const TAG = "ee895";
 
+// Serial number is 16 bytes
+static constexpr size_t EE895_SERIAL_NUMBER_SIZE = 16;
+
 static const uint16_t CRC16_ONEWIRE_START = 0xFFFF;
 static const uint8_t FUNCTION_CODE_READ = 0x03;
 static const uint16_t SERIAL_NUMBER = 0x0000;
@@ -26,7 +29,10 @@ void EE895Component::setup() {
     this->mark_failed();
     return;
   }
-  ESP_LOGV(TAG, "    Serial Number: 0x%s", format_hex(serial_number + 2, 16).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  char serial_hex[format_hex_size(EE895_SERIAL_NUMBER_SIZE)];
+#endif
+  ESP_LOGV(TAG, "    Serial Number: 0x%s", format_hex_to(serial_hex, serial_number + 2, EE895_SERIAL_NUMBER_SIZE));
 }
 
 void EE895Component::dump_config() {

esphome/components/epaper_spi/epaper_spi.cpp

@@ -7,6 +7,7 @@
 namespace esphome::epaper_spi {
 
 static const char *const TAG = "epaper_spi";
+static constexpr size_t EPAPER_MAX_CMD_LOG_BYTES = 128;
 
 static constexpr const char *const EPAPER_STATE_STRINGS[] = {
     "IDLE",          "UPDATE",   "RESET",          "RESET_END", "SHOULD_WAIT", "INITIALISE",
@@ -68,8 +69,11 @@ void EPaperBase::data(uint8_t value) {
 // The command is the first byte, length is the length of data only in the second byte, followed by the data.
 // [COMMAND, LENGTH, DATA...]
 void EPaperBase::cmd_data(uint8_t command, const uint8_t *ptr, size_t length) {
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  char hex_buf[format_hex_pretty_size(EPAPER_MAX_CMD_LOG_BYTES)];
   ESP_LOGV(TAG, "Command: 0x%02X, Length: %d, Data: %s", command, length,
-           format_hex_pretty(ptr, length, '.', false).c_str());
+           format_hex_pretty_to(hex_buf, ptr, length, '.'));
+#endif
 
   this->dc_pin_->digital_write(false);
   this->enable();

esphome/components/esp32/__init__.py

@@ -85,6 +85,7 @@ CONF_ENABLE_IDF_EXPERIMENTAL_FEATURES = "enable_idf_experimental_features"
 CONF_ENABLE_LWIP_ASSERT = "enable_lwip_assert"
 CONF_ENABLE_OTA_ROLLBACK = "enable_ota_rollback"
 CONF_EXECUTE_FROM_PSRAM = "execute_from_psram"
+CONF_MINIMUM_CHIP_REVISION = "minimum_chip_revision"
 CONF_RELEASE = "release"
 
 LOG_LEVELS_IDF = [
@@ -109,6 +110,21 @@ COMPILER_OPTIMIZATIONS = {
     "SIZE": "CONFIG_COMPILER_OPTIMIZATION_SIZE",
 }
 
+# ESP32 (original) chip revision options
+# Setting minimum revision to 3.0 or higher:
+# - Reduces flash size by excluding workaround code for older chip bugs
+# - For PSRAM users: disables CONFIG_SPIRAM_CACHE_WORKAROUND, which saves significant
+#   IRAM by keeping C library functions in ROM instead of recompiling them
+# See: https://docs.espressif.com/projects/esp-idf/en/stable/esp32/api-reference/system/chip_revision.html
+ESP32_CHIP_REVISIONS = {
+    "0.0": "CONFIG_ESP32_REV_MIN_0",
+    "1.0": "CONFIG_ESP32_REV_MIN_1",
+    "1.1": "CONFIG_ESP32_REV_MIN_1_1",
+    "2.0": "CONFIG_ESP32_REV_MIN_2",
+    "3.0": "CONFIG_ESP32_REV_MIN_3",
+    "3.1": "CONFIG_ESP32_REV_MIN_3_1",
+}
+
 # Socket limit configuration for ESP-IDF
 # ESP-IDF CONFIG_LWIP_MAX_SOCKETS has range 1-253, default 10
 DEFAULT_MAX_SOCKETS = 10  # ESP-IDF default
@@ -357,11 +373,12 @@ def _is_framework_url(source: str) -> bool:
 # The default/recommended arduino framework version
 #  - https://github.com/espressif/arduino-esp32/releases
 ARDUINO_FRAMEWORK_VERSION_LOOKUP = {
-    "recommended": cv.Version(3, 3, 2),
-    "latest": cv.Version(3, 3, 4),
-    "dev": cv.Version(3, 3, 4),
+    "recommended": cv.Version(3, 3, 5),
+    "latest": cv.Version(3, 3, 5),
+    "dev": cv.Version(3, 3, 5),
 }
 ARDUINO_PLATFORM_VERSION_LOOKUP = {
+    cv.Version(3, 3, 5): cv.Version(55, 3, 35),
     cv.Version(3, 3, 4): cv.Version(55, 3, 31, "2"),
     cv.Version(3, 3, 3): cv.Version(55, 3, 31, "2"),
     cv.Version(3, 3, 2): cv.Version(55, 3, 31, "2"),
@@ -374,15 +391,33 @@ ARDUINO_PLATFORM_VERSION_LOOKUP = {
     cv.Version(3, 1, 1): cv.Version(53, 3, 11),
     cv.Version(3, 1, 0): cv.Version(53, 3, 10),
 }
+# Maps Arduino framework versions to a compatible ESP-IDF version
+# These versions correspond to pioarduino/esp-idf releases
+# See: https://github.com/pioarduino/esp-idf/releases
+ARDUINO_IDF_VERSION_LOOKUP = {
+    cv.Version(3, 3, 5): cv.Version(5, 5, 2),
+    cv.Version(3, 3, 4): cv.Version(5, 5, 1),
+    cv.Version(3, 3, 3): cv.Version(5, 5, 1),
+    cv.Version(3, 3, 2): cv.Version(5, 5, 1),
+    cv.Version(3, 3, 1): cv.Version(5, 5, 1),
+    cv.Version(3, 3, 0): cv.Version(5, 5, 0),
+    cv.Version(3, 2, 1): cv.Version(5, 4, 2),
+    cv.Version(3, 2, 0): cv.Version(5, 4, 2),
+    cv.Version(3, 1, 3): cv.Version(5, 3, 2),
+    cv.Version(3, 1, 2): cv.Version(5, 3, 2),
+    cv.Version(3, 1, 1): cv.Version(5, 3, 1),
+    cv.Version(3, 1, 0): cv.Version(5, 3, 0),
+}
 
 # The default/recommended esp-idf framework version
 #  - https://github.com/espressif/esp-idf/releases
 ESP_IDF_FRAMEWORK_VERSION_LOOKUP = {
-    "recommended": cv.Version(5, 5, 1),
-    "latest": cv.Version(5, 5, 1),
-    "dev": cv.Version(5, 5, 1),
+    "recommended": cv.Version(5, 5, 2),
+    "latest": cv.Version(5, 5, 2),
+    "dev": cv.Version(5, 5, 2),
 }
 ESP_IDF_PLATFORM_VERSION_LOOKUP = {
+    cv.Version(5, 5, 2): cv.Version(55, 3, 35),
     cv.Version(5, 5, 1): cv.Version(55, 3, 31, "2"),
     cv.Version(5, 5, 0): cv.Version(55, 3, 31, "2"),
     cv.Version(5, 4, 3): cv.Version(55, 3, 32),
@@ -399,9 +434,9 @@ ESP_IDF_PLATFORM_VERSION_LOOKUP = {
 # The platform-espressif32 version
 #  - https://github.com/pioarduino/platform-espressif32/releases
 PLATFORM_VERSION_LOOKUP = {
-    "recommended": cv.Version(55, 3, 31, "2"),
-    "latest": cv.Version(55, 3, 31, "2"),
-    "dev": cv.Version(55, 3, 31, "2"),
+    "recommended": cv.Version(55, 3, 35),
+    "latest": cv.Version(55, 3, 35),
+    "dev": cv.Version(55, 3, 35),
 }
 
 
@@ -547,6 +582,16 @@ def final_validate(config):
                 path=[CONF_FRAMEWORK, CONF_ADVANCED, CONF_IGNORE_EFUSE_MAC_CRC],
             )
         )
+    if (
+        config[CONF_VARIANT] != VARIANT_ESP32
+        and advanced.get(CONF_MINIMUM_CHIP_REVISION) is not None
+    ):
+        errs.append(
+            cv.Invalid(
+                f"'{CONF_MINIMUM_CHIP_REVISION}' is only supported on {VARIANT_ESP32}",
+                path=[CONF_FRAMEWORK, CONF_ADVANCED, CONF_MINIMUM_CHIP_REVISION],
+            )
+        )
     if advanced[CONF_EXECUTE_FROM_PSRAM]:
         if config[CONF_VARIANT] != VARIANT_ESP32S3:
             errs.append(
@@ -689,6 +734,9 @@ FRAMEWORK_SCHEMA = cv.Schema(
                 cv.Optional(CONF_ENABLE_LWIP_ASSERT, default=True): cv.boolean,
                 cv.Optional(CONF_IGNORE_EFUSE_CUSTOM_MAC, default=False): cv.boolean,
                 cv.Optional(CONF_IGNORE_EFUSE_MAC_CRC, default=False): cv.boolean,
+                cv.Optional(CONF_MINIMUM_CHIP_REVISION): cv.one_of(
+                    *ESP32_CHIP_REVISIONS
+                ),
                 # DHCP server is needed for WiFi AP mode. When WiFi component is used,
                 # it will handle disabling DHCP server when AP is not configured.
                 # Default to false (disabled) when WiFi is not used.
@@ -741,12 +789,14 @@ FRAMEWORK_SCHEMA = cv.Schema(
 )
 
 
+# Remove this class in 2026.7.0
 class _FrameworkMigrationWarning:
     shown = False
 
 
 def _show_framework_migration_message(name: str, variant: str) -> None:
-    """Show a friendly message about framework migration when defaulting to Arduino."""
+    """Show a message about the framework default change and how to switch back to Arduino."""
+    # Remove this function in 2026.7.0
     if _FrameworkMigrationWarning.shown:
         return
     _FrameworkMigrationWarning.shown = True
@@ -756,41 +806,27 @@ def _show_framework_migration_message(name: str, variant: str) -> None:
     message = (
         color(
             AnsiFore.BOLD_CYAN,
-            f"💡 IMPORTANT: {name} doesn't have a framework specified!",
+            f"💡 NOTICE: {name} does not have a framework specified.",
         )
         + "\n\n"
-        + f"Currently, {variant} defaults to the Arduino framework.\n"
-        + color(AnsiFore.YELLOW, "This will change to ESP-IDF in ESPHome 2026.1.0.\n")
+        + f"Starting with ESPHome 2026.1.0, the default framework for {variant} is ESP-IDF.\n"
+        + "(We've been warning about this change since ESPHome 2025.8.0)\n"
         + "\n"
-        + "Note: Newer ESP32 variants (C6, H2, P4, etc.) already use ESP-IDF by default.\n"
-        + "\n"
-        + "Why change? ESP-IDF offers:\n"
-        + color(AnsiFore.GREEN, "  ✨ Up to 40% smaller binaries\n")
-        + color(AnsiFore.GREEN, "  🚀 Better performance and optimization\n")
+        + "Why we made this change:\n"
+        + color(AnsiFore.GREEN, "  ✨ Up to 40% smaller firmware binaries\n")
         + color(AnsiFore.GREEN, "  ⚡ 2-3x faster compile times\n")
-        + color(AnsiFore.GREEN, "  📦 Custom-built firmware for your exact needs\n")
-        + color(
-            AnsiFore.GREEN,
-            "  🔧 Active development and testing by ESPHome developers\n",
-        )
+        + color(AnsiFore.GREEN, "  🚀 Better performance and newer features\n")
+        + color(AnsiFore.GREEN, "  🔧 More actively maintained by ESPHome\n")
         + "\n"
-        + "Trade-offs:\n"
-        + color(AnsiFore.YELLOW, "  🔄 Some components need migration\n")
+        + "To continue using Arduino, add this to your YAML under 'esp32:':\n"
+        + color(AnsiFore.WHITE, "    framework:\n")
+        + color(AnsiFore.WHITE, "      type: arduino\n")
         + "\n"
-        + "What should I do?\n"
-        + color(AnsiFore.CYAN, "  Option 1")
-        + ": Migrate to ESP-IDF (recommended)\n"
-        + "    Add this to your YAML under 'esp32:':\n"
-        + color(AnsiFore.WHITE, "      framework:\n")
-        + color(AnsiFore.WHITE, "        type: esp-idf\n")
+        + "To silence this message with ESP-IDF, explicitly set:\n"
+        + color(AnsiFore.WHITE, "    framework:\n")
+        + color(AnsiFore.WHITE, "      type: esp-idf\n")
         + "\n"
-        + color(AnsiFore.CYAN, "  Option 2")
-        + ": Keep using Arduino (still supported)\n"
-        + "    Add this to your YAML under 'esp32:':\n"
-        + color(AnsiFore.WHITE, "      framework:\n")
-        + color(AnsiFore.WHITE, "        type: arduino\n")
-        + "\n"
-        + "Need help? Check out the migration guide:\n"
+        + "Migration guide: "
         + color(
             AnsiFore.BLUE,
             "https://esphome.io/guides/esp32_arduino_to_idf/",
@@ -805,13 +841,13 @@ def _set_default_framework(config):
         config[CONF_FRAMEWORK] = FRAMEWORK_SCHEMA({})
     if CONF_TYPE not in config[CONF_FRAMEWORK]:
         variant = config[CONF_VARIANT]
+        config[CONF_FRAMEWORK][CONF_TYPE] = FRAMEWORK_ESP_IDF
+        # Show migration message for variants that previously defaulted to Arduino
+        # Remove this message in 2026.7.0
         if variant in ARDUINO_ALLOWED_VARIANTS:
-            config[CONF_FRAMEWORK][CONF_TYPE] = FRAMEWORK_ARDUINO
             _show_framework_migration_message(
                 config.get(CONF_NAME, "This device"), variant
             )
-        else:
-            config[CONF_FRAMEWORK][CONF_TYPE] = FRAMEWORK_ESP_IDF
 
     return config
 
@@ -1005,6 +1041,13 @@ async def to_code(config):
         add_idf_sdkconfig_option("CONFIG_MBEDTLS_PSK_MODES", True)
         add_idf_sdkconfig_option("CONFIG_MBEDTLS_CERTIFICATE_BUNDLE", True)
 
+        # Add IDF framework source for Arduino builds to ensure it uses the same version as
+        # the ESP-IDF framework
+        if (idf_ver := ARDUINO_IDF_VERSION_LOOKUP.get(framework_ver)) is not None:
+            cg.add_platformio_option(
+                "platform_packages", [_format_framework_espidf_version(idf_ver, None)]
+            )
+
         # ESP32-S2 Arduino: Disable USB Serial on boot to avoid TinyUSB dependency
         if get_esp32_variant() == VARIANT_ESP32S2:
             cg.add_build_unflag("-DARDUINO_USB_CDC_ON_BOOT=1")
@@ -1017,6 +1060,16 @@ async def to_code(config):
     add_idf_sdkconfig_option(
         f"CONFIG_ESPTOOLPY_FLASHSIZE_{config[CONF_FLASH_SIZE]}", True
     )
+
+    # Set minimum chip revision for ESP32 variant
+    # Setting this to 3.0 or higher reduces flash size by excluding workaround code,
+    # and for PSRAM users saves significant IRAM by keeping C library functions in ROM.
+    if variant == VARIANT_ESP32:
+        min_rev = conf[CONF_ADVANCED].get(CONF_MINIMUM_CHIP_REVISION)
+        if min_rev is not None:
+            for rev, flag in ESP32_CHIP_REVISIONS.items():
+                add_idf_sdkconfig_option(flag, rev == min_rev)
+            cg.add_define("USE_ESP32_MIN_CHIP_REVISION_SET")
     add_idf_sdkconfig_option("CONFIG_PARTITION_TABLE_SINGLE_APP", False)
     add_idf_sdkconfig_option("CONFIG_PARTITION_TABLE_CUSTOM", True)
     add_idf_sdkconfig_option("CONFIG_PARTITION_TABLE_CUSTOM_FILENAME", "partitions.csv")

esphome/components/esp32/boards.py

@@ -1488,6 +1488,10 @@ BOARDS = {
         "name": "Arduino Nano ESP32",
         "variant": VARIANT_ESP32S3,
     },
+    "arduino_nesso_n1": {
+        "name": "Arduino Nesso-N1",
+        "variant": VARIANT_ESP32C6,
+    },
     "atd147_s3": {
         "name": "ArtronShop ATD1.47-S3",
         "variant": VARIANT_ESP32S3,
@@ -1656,6 +1660,10 @@ BOARDS = {
         "name": "Espressif ESP32-C6-DevKitM-1",
         "variant": VARIANT_ESP32C6,
     },
+    "esp32-c61-devkitc1-n8r2": {
+        "name": "Espressif ESP32-C61-DevKitC-1 N8R2 (8 MB Flash Quad, 2 MB PSRAM Quad)",
+        "variant": VARIANT_ESP32C61,
+    },
     "esp32-devkitlipo": {
         "name": "OLIMEX ESP32-DevKit-LiPo",
         "variant": VARIANT_ESP32,
@@ -1673,11 +1681,15 @@ BOARDS = {
         "variant": VARIANT_ESP32H2,
     },
     "esp32-p4": {
-        "name": "Espressif ESP32-P4 generic",
+        "name": "Espressif ESP32-P4 ES (pre rev.300) generic",
         "variant": VARIANT_ESP32P4,
     },
     "esp32-p4-evboard": {
-        "name": "Espressif ESP32-P4 Function EV Board",
+        "name": "Espressif ESP32-P4 Function EV Board (ES pre rev.300)",
+        "variant": VARIANT_ESP32P4,
+    },
+    "esp32-p4_r3": {
+        "name": "Espressif ESP32-P4 rev.300 generic",
         "variant": VARIANT_ESP32P4,
     },
     "esp32-pico-devkitm-2": {
@@ -2093,7 +2105,7 @@ BOARDS = {
         "variant": VARIANT_ESP32,
     },
     "m5stack-tab5-p4": {
-        "name": "M5STACK Tab5 esp32-p4 Board",
+        "name": "M5STACK Tab5 esp32-p4 Board (ES pre rev.300)",
         "variant": VARIANT_ESP32P4,
     },
     "m5stack-timer-cam": {

esphome/components/esp32/gpio.cpp

@@ -97,10 +97,8 @@ void ESP32InternalGPIOPin::attach_interrupt(void (*func)(void *), void *arg, gpi
   gpio_intr_enable(this->get_pin_num());
 }
 
-std::string ESP32InternalGPIOPin::dump_summary() const {
-  char buffer[32];
-  snprintf(buffer, sizeof(buffer), "GPIO%" PRIu32, static_cast<uint32_t>(this->pin_));
-  return buffer;
+size_t ESP32InternalGPIOPin::dump_summary(char *buffer, size_t len) const {
+  return snprintf(buffer, len, "GPIO%" PRIu32, static_cast<uint32_t>(this->pin_));
 }
 
 void ESP32InternalGPIOPin::setup() {

esphome/components/esp32/gpio.h

@@ -24,7 +24,7 @@ class ESP32InternalGPIOPin : public InternalGPIOPin {
   void pin_mode(gpio::Flags flags) override;
   bool digital_read() override;
   void digital_write(bool value) override;
-  std::string dump_summary() const override;
+  size_t dump_summary(char *buffer, size_t len) const override;
   void detach_interrupt() const override;
   ISRInternalGPIOPin to_isr() const override;
   uint8_t get_pin() const override { return this->pin_; }

esphome/components/esp32_ble/ble.cpp

@@ -24,7 +24,9 @@ extern "C" {
 #include <nvs_flash.h>
 
 #ifdef USE_ARDUINO
-#include <esp32-hal-bt.h>
+// Prevent Arduino from releasing BT memory at startup (esp32-hal-misc.c).
+// Without this, esp_bt_controller_init() fails with ESP_ERR_INVALID_STATE.
+extern "C" bool btInUse() { return true; }  // NOLINT(readability-identifier-naming)
 #endif
 
 namespace esphome::esp32_ble {
@@ -169,12 +171,6 @@ void ESP32BLE::advertising_init_() {
 bool ESP32BLE::ble_setup_() {
   esp_err_t err;
 #ifndef CONFIG_ESP_HOSTED_ENABLE_BT_BLUEDROID
-#ifdef USE_ARDUINO
-  if (!btStart()) {
-    ESP_LOGE(TAG, "btStart failed: %d", esp_bt_controller_get_status());
-    return false;
-  }
-#else
   if (esp_bt_controller_get_status() != ESP_BT_CONTROLLER_STATUS_ENABLED) {
     // start bt controller
     if (esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_IDLE) {
@@ -199,7 +195,6 @@ bool ESP32BLE::ble_setup_() {
       return false;
     }
   }
-#endif
 
   esp_bt_controller_mem_release(ESP_BT_MODE_CLASSIC_BT);
 #else
@@ -338,12 +333,6 @@ bool ESP32BLE::ble_dismantle_() {
   }
 
 #ifndef CONFIG_ESP_HOSTED_ENABLE_BT_BLUEDROID
-#ifdef USE_ARDUINO
-  if (!btStop()) {
-    ESP_LOGE(TAG, "btStop failed: %d", esp_bt_controller_get_status());
-    return false;
-  }
-#else
   if (esp_bt_controller_get_status() != ESP_BT_CONTROLLER_STATUS_IDLE) {
     // stop bt controller
     if (esp_bt_controller_get_status() == ESP_BT_CONTROLLER_STATUS_ENABLED) {
@@ -367,7 +356,6 @@ bool ESP32BLE::ble_dismantle_() {
       return false;
     }
   }
-#endif
 #else
   if (esp_hosted_bt_controller_disable() != ESP_OK) {
     ESP_LOGW(TAG, "esp_hosted_bt_controller_disable failed");

esphome/components/esp32_ble_tracker/esp32_ble_tracker.cpp

@@ -37,6 +37,9 @@ namespace esphome::esp32_ble_tracker {
 
 static const char *const TAG = "esp32_ble_tracker";
 
+// BLE advertisement max: 31 bytes adv data + 31 bytes scan response
+static constexpr size_t BLE_ADV_MAX_LOG_BYTES = 62;
+
 ESP32BLETracker *global_esp32_ble_tracker = nullptr;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
 
 const char *client_state_to_string(ClientState state) {
@@ -445,6 +448,7 @@ void ESPBTDevice::parse_scan_rst(const BLEScanResult &scan_result) {
     uuid.to_str(uuid_buf);
     ESP_LOGVV(TAG, "  Service UUID: %s", uuid_buf);
   }
+  char hex_buf[format_hex_pretty_size(BLE_ADV_MAX_LOG_BYTES)];
   for (auto &data : this->manufacturer_datas_) {
     auto ibeacon = ESPBLEiBeacon::from_manufacturer_data(data);
     if (ibeacon.has_value()) {
@@ -458,7 +462,8 @@ void ESPBTDevice::parse_scan_rst(const BLEScanResult &scan_result) {
     } else {
       char uuid_buf[esp32_ble::UUID_STR_LEN];
       data.uuid.to_str(uuid_buf);
-      ESP_LOGVV(TAG, "  Manufacturer ID: %s, data: %s", uuid_buf, format_hex_pretty(data.data).c_str());
+      ESP_LOGVV(TAG, "  Manufacturer ID: %s, data: %s", uuid_buf,
+                format_hex_pretty_to(hex_buf, data.data.data(), data.data.size()));
     }
   }
   for (auto &data : this->service_datas_) {
@@ -466,11 +471,11 @@ void ESPBTDevice::parse_scan_rst(const BLEScanResult &scan_result) {
     char uuid_buf[esp32_ble::UUID_STR_LEN];
     data.uuid.to_str(uuid_buf);
     ESP_LOGVV(TAG, "    UUID: %s", uuid_buf);
-    ESP_LOGVV(TAG, "    Data: %s", format_hex_pretty(data.data).c_str());
+    ESP_LOGVV(TAG, "    Data: %s", format_hex_pretty_to(hex_buf, data.data.data(), data.data.size()));
   }
 
   ESP_LOGVV(TAG, "  Adv data: %s",
-            format_hex_pretty(scan_result.ble_adv, scan_result.adv_data_len + scan_result.scan_rsp_len).c_str());
+            format_hex_pretty_to(hex_buf, scan_result.ble_adv, scan_result.adv_data_len + scan_result.scan_rsp_len));
 #endif
 }
 

esphome/components/esp32_improv/esp32_improv_component.cpp

@@ -4,6 +4,7 @@
 #include "esphome/components/esp32_ble/ble.h"
 #include "esphome/components/esp32_ble_server/ble_2902.h"
 #include "esphome/core/application.h"
+#include "esphome/core/helpers.h"
 #include "esphome/core/log.h"
 
 #ifdef USE_ESP32
@@ -14,6 +15,7 @@ namespace esp32_improv {
 using namespace bytebuffer;
 
 static const char *const TAG = "esp32_improv.component";
+static constexpr size_t IMPROV_MAX_LOG_BYTES = 128;
 static const char *const ESPHOME_MY_LINK = "https://my.home-assistant.io/redirect/config_flow_start?domain=esphome";
 static constexpr uint16_t STOP_ADVERTISING_DELAY =
     10000;  // Delay (ms) before stopping service to allow BLE clients to read the final state
@@ -314,7 +316,11 @@ void ESP32ImprovComponent::dump_config() {
 void ESP32ImprovComponent::process_incoming_data_() {
   uint8_t length = this->incoming_data_[1];
 
-  ESP_LOGV(TAG, "Processing bytes - %s", format_hex_pretty(this->incoming_data_).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  char hex_buf[format_hex_pretty_size(IMPROV_MAX_LOG_BYTES)];
+  ESP_LOGV(TAG, "Processing bytes - %s",
+           format_hex_pretty_to(hex_buf, this->incoming_data_.data(), this->incoming_data_.size()));
+#endif
   if (this->incoming_data_.size() - 3 == length) {
     this->set_error_(improv::ERROR_NONE);
     improv::ImprovCommand command = improv::parse_improv_data(this->incoming_data_);
@@ -403,8 +409,12 @@ void ESP32ImprovComponent::check_wifi_connection_() {
 #ifdef USE_WEBSERVER
     for (auto &ip : wifi::global_wifi_component->wifi_sta_ip_addresses()) {
       if (ip.is_ip4()) {
-        char url_buffer[64];
-        snprintf(url_buffer, sizeof(url_buffer), "http://%s:%d", ip.str().c_str(), USE_WEBSERVER_PORT);
+        // "http://" (7) + IPv4 max (15) + ":" (1) + port max (5) + null = 29
+        char url_buffer[32];
+        memcpy(url_buffer, "http://", 7);  // NOLINT(bugprone-not-null-terminated-result) - str_to null-terminates
+        ip.str_to(url_buffer + 7);
+        size_t len = strlen(url_buffer);
+        snprintf(url_buffer + len, sizeof(url_buffer) - len, ":%d", USE_WEBSERVER_PORT);
         url_strings[url_count++] = url_buffer;
         break;
       }

esphome/components/esp8266/__init__.py

@@ -28,6 +28,7 @@ from .const import (
     KEY_ESP8266,
     KEY_FLASH_SIZE,
     KEY_PIN_INITIAL_STATES,
+    KEY_WAVEFORM_REQUIRED,
     esp8266_ns,
 )
 from .gpio import PinInitialState, add_pin_initial_states_array
@@ -191,7 +192,13 @@ async def to_code(config):
     cg.add_define(ThreadModel.SINGLE)
 
     cg.add_platformio_option(
-        "extra_scripts", ["pre:testing_mode.py", "post:post_build.py"]
+        "extra_scripts",
+        [
+            "pre:testing_mode.py",
+            "pre:exclude_updater.py",
+            "pre:exclude_waveform.py",
+            "post:post_build.py",
+        ],
     )
 
     conf = config[CONF_FRAMEWORK]
@@ -263,10 +270,24 @@ async def to_code(config):
             cg.add_platformio_option("board_build.ldscript", ld_script)
 
     CORE.add_job(add_pin_initial_states_array)
+    CORE.add_job(finalize_waveform_config)
+
+
+@coroutine_with_priority(CoroPriority.WORKAROUNDS)
+async def finalize_waveform_config() -> None:
+    """Add waveform stubs define if waveform is not required.
+
+    This runs at WORKAROUNDS priority (-999) to ensure all components
+    have had a chance to call require_waveform() first.
+    """
+    if not CORE.data.get(KEY_ESP8266, {}).get(KEY_WAVEFORM_REQUIRED, False):
+        # No component needs waveform - enable stubs and exclude Arduino waveform code
+        # Use build flag (visible to both C++ code and PlatformIO script)
+        cg.add_build_flag("-DUSE_ESP8266_WAVEFORM_STUBS")
 
 
 # Called by writer.py
-def copy_files():
+def copy_files() -> None:
     dir = Path(__file__).parent
     post_build_file = dir / "post_build.py.script"
     copy_file_if_changed(
@@ -278,3 +299,13 @@ def copy_files():
         testing_mode_file,
         CORE.relative_build_path("testing_mode.py"),
     )
+    exclude_updater_file = dir / "exclude_updater.py.script"
+    copy_file_if_changed(
+        exclude_updater_file,
+        CORE.relative_build_path("exclude_updater.py"),
+    )
+    exclude_waveform_file = dir / "exclude_waveform.py.script"
+    copy_file_if_changed(
+        exclude_waveform_file,
+        CORE.relative_build_path("exclude_waveform.py"),
+    )

esphome/components/esp8266/const.py

@@ -1,4 +1,5 @@
 import esphome.codegen as cg
+from esphome.core import CORE
 
 KEY_ESP8266 = "esp8266"
 KEY_BOARD = "board"
@@ -6,6 +7,25 @@ KEY_PIN_INITIAL_STATES = "pin_initial_states"
 CONF_RESTORE_FROM_FLASH = "restore_from_flash"
 CONF_EARLY_PIN_INIT = "early_pin_init"
 KEY_FLASH_SIZE = "flash_size"
+KEY_WAVEFORM_REQUIRED = "waveform_required"
 
 # esp8266 namespace is already defined by arduino, manually prefix esphome
 esp8266_ns = cg.global_ns.namespace("esphome").namespace("esp8266")
+
+
+def require_waveform() -> None:
+    """Mark that Arduino waveform/PWM support is required.
+
+    Call this from components that need the Arduino waveform generator
+    (startWaveform, stopWaveform, analogWrite, Tone, Servo).
+
+    If no component calls this, the waveform code is excluded from the build
+    to save ~596 bytes of RAM and 464 bytes of flash.
+
+    Example:
+        from esphome.components.esp8266.const import require_waveform
+
+        async def to_code(config):
+            require_waveform()
+    """
+    CORE.data.setdefault(KEY_ESP8266, {})[KEY_WAVEFORM_REQUIRED] = True

esphome/components/esp8266/exclude_updater.py.script

@@ -0,0 +1,21 @@
+# pylint: disable=E0602
+Import("env")  # noqa
+
+import os
+
+# Filter out Updater.cpp from the Arduino core build
+# This saves 228 bytes of .bss by not instantiating the global Update object
+# ESPHome uses its own native OTA backend instead
+
+
+def filter_updater_from_core(env, node):
+    """Filter callback to exclude Updater.cpp from framework build."""
+    path = node.get_path()
+    if path.endswith("Updater.cpp"):
+        print(f"ESPHome: Excluding {os.path.basename(path)} from build (using native OTA backend)")
+        return None
+    return node
+
+
+# Apply the filter to framework sources
+env.AddBuildMiddleware(filter_updater_from_core, "**/cores/esp8266/Updater.cpp")

esphome/components/esp8266/exclude_waveform.py.script

@@ -0,0 +1,50 @@
+# pylint: disable=E0602
+Import("env")  # noqa
+
+import os
+
+# Filter out waveform/PWM code from the Arduino core build
+# This saves ~596 bytes of RAM and 464 bytes of flash by not
+# instantiating the waveform generator state structures (wvfState + pwmState).
+#
+# The waveform code is used by: analogWrite, Tone, Servo, and direct
+# startWaveform/stopWaveform calls. ESPHome's esp8266_pwm component
+# calls require_waveform() to keep this code when needed.
+#
+# When excluded, we provide stub implementations of stopWaveform() and
+# _stopPWM() since digitalWrite() calls these unconditionally.
+
+
+def has_define_flag(env, name):
+    """Check if a define exists in the build flags."""
+    define_flag = f"-D{name}"
+    # Check BUILD_FLAGS (where ESPHome puts its defines)
+    for flag in env.get("BUILD_FLAGS", []):
+        if flag == define_flag or flag.startswith(f"{define_flag}="):
+            return True
+    # Also check CPPDEFINES list (parsed defines)
+    for define in env.get("CPPDEFINES", []):
+        if isinstance(define, tuple):
+            if define[0] == name:
+                return True
+        elif define == name:
+            return True
+    return False
+
+# USE_ESP8266_WAVEFORM_STUBS is defined when no component needs waveform
+if has_define_flag(env, "USE_ESP8266_WAVEFORM_STUBS"):
+
+    def filter_waveform_from_core(env, node):
+        """Filter callback to exclude waveform files from framework build."""
+        path = node.get_path()
+        filename = os.path.basename(path)
+        if filename in (
+            "core_esp8266_waveform_pwm.cpp",
+            "core_esp8266_waveform_phase.cpp",
+        ):
+            print(f"ESPHome: Excluding {filename} from build (waveform not required)")
+            return None
+        return node
+
+    # Apply the filter to framework sources
+    env.AddBuildMiddleware(filter_waveform_from_core, "**/cores/esp8266/*.cpp")

esphome/components/esp8266/gpio.cpp

@@ -98,10 +98,8 @@ void ESP8266GPIOPin::pin_mode(gpio::Flags flags) {
   pinMode(pin_, flags_to_mode(flags, pin_));  // NOLINT
 }
 
-std::string ESP8266GPIOPin::dump_summary() const {
-  char buffer[32];
-  snprintf(buffer, sizeof(buffer), "GPIO%u", pin_);
-  return buffer;
+size_t ESP8266GPIOPin::dump_summary(char *buffer, size_t len) const {
+  return snprintf(buffer, len, "GPIO%u", this->pin_);
 }
 
 bool ESP8266GPIOPin::digital_read() {

esphome/components/esp8266/gpio.h

@@ -17,7 +17,7 @@ class ESP8266GPIOPin : public InternalGPIOPin {
   void pin_mode(gpio::Flags flags) override;
   bool digital_read() override;
   void digital_write(bool value) override;
-  std::string dump_summary() const override;
+  size_t dump_summary(char *buffer, size_t len) const override;
   void detach_interrupt() const override;
   ISRInternalGPIOPin to_isr() const override;
   uint8_t get_pin() const override { return pin_; }

esphome/components/esp8266/waveform_stubs.cpp

@@ -0,0 +1,34 @@
+#ifdef USE_ESP8266_WAVEFORM_STUBS
+
+// Stub implementations for Arduino waveform/PWM functions.
+//
+// When the waveform generator is not needed (no esp8266_pwm component),
+// we exclude core_esp8266_waveform_pwm.cpp from the build to save ~596 bytes
+// of RAM and 464 bytes of flash.
+//
+// These stubs satisfy calls from the Arduino GPIO code when the real
+// waveform implementation is excluded. They must be in the global namespace
+// with C linkage to match the Arduino core function declarations.
+
+#include <cstdint>
+
+// Empty namespace to satisfy linter - actual stubs must be at global scope
+namespace esphome::esp8266 {}  // namespace esphome::esp8266
+
+extern "C" {
+
+// Called by Arduino GPIO code to stop any waveform on a pin
+int stopWaveform(uint8_t pin) {
+  (void) pin;
+  return 1;  // Success (no waveform to stop)
+}
+
+// Called by Arduino GPIO code to stop any PWM on a pin
+bool _stopPWM(uint8_t pin) {
+  (void) pin;
+  return false;  // No PWM was running
+}
+
+}  // extern "C"
+
+#endif  // USE_ESP8266_WAVEFORM_STUBS

esphome/components/esp8266_pwm/output.py

@@ -1,6 +1,7 @@
 from esphome import automation, pins
 import esphome.codegen as cg
 from esphome.components import output
+from esphome.components.esp8266.const import require_waveform
 import esphome.config_validation as cv
 from esphome.const import CONF_FREQUENCY, CONF_ID, CONF_NUMBER, CONF_PIN
 
@@ -34,7 +35,9 @@ CONFIG_SCHEMA = cv.All(
 )
 
 
-async def to_code(config):
+async def to_code(config) -> None:
+    require_waveform()
+
     var = cg.new_Pvariable(config[CONF_ID])
     await cg.register_component(var, config)
     await output.register_output(var, config)

esphome/components/esp_ldo/__init__.py

@@ -31,7 +31,7 @@ CONFIG_SCHEMA = cv.All(
             }
         )
     ),
-    cv.only_with_esp_idf,
+    cv.only_on_esp32,
     only_on_variant(supported=[VARIANT_ESP32P4]),
 )
 

esphome/components/esphome/ota/__init__.py

@@ -16,7 +16,7 @@ from esphome.const import (
     CONF_SAFE_MODE,
     CONF_VERSION,
 )
-from esphome.core import CORE, coroutine_with_priority
+from esphome.core import coroutine_with_priority
 from esphome.coroutine import CoroPriority
 import esphome.final_validate as fv
 from esphome.types import ConfigType
@@ -28,17 +28,7 @@ CODEOWNERS = ["@esphome/core"]
 DEPENDENCIES = ["network"]
 
 
-def supports_sha256() -> bool:
-    """Check if the current platform supports SHA256 for OTA authentication."""
-    return bool(CORE.is_esp32 or CORE.is_esp8266 or CORE.is_rp2040 or CORE.is_libretiny)
-
-
-def AUTO_LOAD() -> list[str]:
-    """Conditionally auto-load sha256 only on platforms that support it."""
-    base_components = ["md5", "socket"]
-    if supports_sha256():
-        return base_components + ["sha256"]
-    return base_components
+AUTO_LOAD = ["sha256", "socket"]
 
 
 esphome = cg.esphome_ns.namespace("esphome")
@@ -155,11 +145,6 @@ async def to_code(config: ConfigType) -> None:
     if config.get(CONF_PASSWORD):
         cg.add(var.set_auth_password(config[CONF_PASSWORD]))
         cg.add_define("USE_OTA_PASSWORD")
-        # Only include hash algorithms when password is configured
-        cg.add_define("USE_OTA_MD5")
-        # Only include SHA256 support on platforms that have it
-        if supports_sha256():
-            cg.add_define("USE_OTA_SHA256")
     cg.add_define("USE_OTA_VERSION", config[CONF_VERSION])
 
     await cg.register_component(var, config)

esphome/components/esphome/ota/ota_esphome.cpp

@@ -1,16 +1,12 @@
 #include "ota_esphome.h"
 #ifdef USE_OTA
 #ifdef USE_OTA_PASSWORD
-#ifdef USE_OTA_MD5
-#include "esphome/components/md5/md5.h"
-#endif
-#ifdef USE_OTA_SHA256
 #include "esphome/components/sha256/sha256.h"
 #endif
-#endif
 #include "esphome/components/network/util.h"
+#include "esphome/components/socket/socket.h"
 #include "esphome/components/ota/ota_backend.h"
-#include "esphome/components/ota/ota_backend_arduino_esp8266.h"
+#include "esphome/components/ota/ota_backend_esp8266.h"
 #include "esphome/components/ota/ota_backend_arduino_libretiny.h"
 #include "esphome/components/ota/ota_backend_arduino_rp2040.h"
 #include "esphome/components/ota/ota_backend_esp_idf.h"
@@ -31,15 +27,6 @@ static constexpr size_t OTA_BUFFER_SIZE = 1024;                  // buffer size
 static constexpr uint32_t OTA_SOCKET_TIMEOUT_HANDSHAKE = 20000;  // milliseconds for initial handshake
 static constexpr uint32_t OTA_SOCKET_TIMEOUT_DATA = 90000;       // milliseconds for data transfer
 
-#ifdef USE_OTA_PASSWORD
-#ifdef USE_OTA_MD5
-static constexpr size_t MD5_HEX_SIZE = 32;  // MD5 hash as hex string (16 bytes * 2)
-#endif
-#ifdef USE_OTA_SHA256
-static constexpr size_t SHA256_HEX_SIZE = 64;  // SHA256 hash as hex string (32 bytes * 2)
-#endif
-#endif  // USE_OTA_PASSWORD
-
 void ESPHomeOTAComponent::setup() {
   this->server_ = socket::socket_ip_loop_monitored(SOCK_STREAM, 0);  // monitored for incoming connections
   if (this->server_ == nullptr) {
@@ -108,15 +95,7 @@ void ESPHomeOTAComponent::loop() {
 }
 
 static const uint8_t FEATURE_SUPPORTS_COMPRESSION = 0x01;
-#ifdef USE_OTA_SHA256
 static const uint8_t FEATURE_SUPPORTS_SHA256_AUTH = 0x02;
-#endif
-
-// Temporary flag to allow MD5 downgrade for ~3 versions (until 2026.1.0)
-// This allows users to downgrade via OTA if they encounter issues after updating.
-// Without this, users would need to do a serial flash to downgrade.
-// TODO: Remove this flag and all associated code in 2026.1.0
-#define ALLOW_OTA_DOWNGRADE_MD5
 
 void ESPHomeOTAComponent::handle_handshake_() {
   /// Handle the OTA handshake and authentication.
@@ -465,7 +444,9 @@ void ESPHomeOTAComponent::log_socket_error_(const LogString *msg) {
 void ESPHomeOTAComponent::log_read_error_(const LogString *what) { ESP_LOGW(TAG, "Read %s failed", LOG_STR_ARG(what)); }
 
 void ESPHomeOTAComponent::log_start_(const LogString *phase) {
-  ESP_LOGD(TAG, "Starting %s from %s", LOG_STR_ARG(phase), this->client_->getpeername().c_str());
+  char peername[socket::PEERNAME_MAX_LEN];
+  this->client_->getpeername_to(peername);
+  ESP_LOGD(TAG, "Starting %s from %s", LOG_STR_ARG(phase), peername);
 }
 
 void ESPHomeOTAComponent::log_remote_closed_(const LogString *during) {
@@ -547,26 +528,8 @@ void ESPHomeOTAComponent::yield_and_feed_watchdog_() {
 void ESPHomeOTAComponent::log_auth_warning_(const LogString *msg) { ESP_LOGW(TAG, "Auth: %s", LOG_STR_ARG(msg)); }
 
 bool ESPHomeOTAComponent::select_auth_type_() {
-#ifdef USE_OTA_SHA256
   bool client_supports_sha256 = (this->ota_features_ & FEATURE_SUPPORTS_SHA256_AUTH) != 0;
 
-#ifdef ALLOW_OTA_DOWNGRADE_MD5
-  // Allow fallback to MD5 if client doesn't support SHA256
-  if (client_supports_sha256) {
-    this->auth_type_ = ota::OTA_RESPONSE_REQUEST_SHA256_AUTH;
-    return true;
-  }
-#ifdef USE_OTA_MD5
-  this->log_auth_warning_(LOG_STR("Using deprecated MD5"));
-  this->auth_type_ = ota::OTA_RESPONSE_REQUEST_AUTH;
-  return true;
-#else
-  this->log_auth_warning_(LOG_STR("SHA256 required"));
-  this->send_error_and_cleanup_(ota::OTA_RESPONSE_ERROR_AUTH_INVALID);
-  return false;
-#endif  // USE_OTA_MD5
-
-#else   // !ALLOW_OTA_DOWNGRADE_MD5
   // Require SHA256
   if (!client_supports_sha256) {
     this->log_auth_warning_(LOG_STR("SHA256 required"));
@@ -575,20 +538,6 @@ bool ESPHomeOTAComponent::select_auth_type_() {
   }
   this->auth_type_ = ota::OTA_RESPONSE_REQUEST_SHA256_AUTH;
   return true;
-#endif  // ALLOW_OTA_DOWNGRADE_MD5
-
-#else  // !USE_OTA_SHA256
-#ifdef USE_OTA_MD5
-  // Only MD5 available
-  this->auth_type_ = ota::OTA_RESPONSE_REQUEST_AUTH;
-  return true;
-#else
-  // No auth methods available
-  this->log_auth_warning_(LOG_STR("No auth methods available"));
-  this->send_error_and_cleanup_(ota::OTA_RESPONSE_ERROR_AUTH_INVALID);
-  return false;
-#endif  // USE_OTA_MD5
-#endif  // USE_OTA_SHA256
 }
 
 bool ESPHomeOTAComponent::handle_auth_send_() {
@@ -612,31 +561,12 @@ bool ESPHomeOTAComponent::handle_auth_send_() {
     //   [1+hex_size...1+2*hex_size-1]: cnonce (hex_size bytes) - client's nonce
     //   [1+2*hex_size...1+3*hex_size-1]: response (hex_size bytes) - client's hash
 
-    // Declare both hash objects in same stack frame, use pointer to select.
-    // NOTE: Both objects are declared here even though only one is used. This is REQUIRED for ESP32-S3
-    // hardware SHA acceleration - the object must exist in this stack frame for all operations.
-    // Do NOT try to "optimize" by creating the object inside the if block, as it would go out of scope.
-#ifdef USE_OTA_SHA256
-    sha256::SHA256 sha_hasher;
-#endif
-#ifdef USE_OTA_MD5
-    md5::MD5Digest md5_hasher;
-#endif
-    HashBase *hasher = nullptr;
+    // CRITICAL ESP32-S3 HARDWARE SHA ACCELERATION: Hash object must stay in same stack frame
+    // (no passing to other functions). All hash operations must happen in this function.
+    sha256::SHA256 hasher;
 
-#ifdef USE_OTA_SHA256
-    if (this->auth_type_ == ota::OTA_RESPONSE_REQUEST_SHA256_AUTH) {
-      hasher = &sha_hasher;
-    }
-#endif
-#ifdef USE_OTA_MD5
-    if (this->auth_type_ == ota::OTA_RESPONSE_REQUEST_AUTH) {
-      hasher = &md5_hasher;
-    }
-#endif
-
-    const size_t hex_size = hasher->get_size() * 2;
-    const size_t nonce_len = hasher->get_size() / 4;
+    const size_t hex_size = hasher.get_size() * 2;
+    const size_t nonce_len = hasher.get_size() / 4;
     const size_t auth_buf_size = 1 + 3 * hex_size;
     this->auth_buf_ = std::make_unique<uint8_t[]>(auth_buf_size);
     this->auth_buf_pos_ = 0;
@@ -648,22 +578,17 @@ bool ESPHomeOTAComponent::handle_auth_send_() {
       return false;
     }
 
-    hasher->init();
-    hasher->add(buf, nonce_len);
-    hasher->calculate();
+    hasher.init();
+    hasher.add(buf, nonce_len);
+    hasher.calculate();
     this->auth_buf_[0] = this->auth_type_;
-    hasher->get_hex(buf);
+    hasher.get_hex(buf);
 
-#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
-    char log_buf[65];  // Fixed size for SHA256 hex (64) + null, works for MD5 (32) too
-    memcpy(log_buf, buf, hex_size);
-    log_buf[hex_size] = '\0';
-    ESP_LOGV(TAG, "Auth: Nonce is %s", log_buf);
-#endif
+    ESP_LOGV(TAG, "Auth: Nonce is %.*s", hex_size, buf);
   }
 
   // Try to write auth_type + nonce
-  size_t hex_size = this->get_auth_hex_size_();
+  constexpr size_t hex_size = SHA256_HEX_SIZE;
   const size_t to_write = 1 + hex_size;
   size_t remaining = to_write - this->auth_buf_pos_;
 
@@ -685,7 +610,7 @@ bool ESPHomeOTAComponent::handle_auth_send_() {
 }
 
 bool ESPHomeOTAComponent::handle_auth_read_() {
-  size_t hex_size = this->get_auth_hex_size_();
+  constexpr size_t hex_size = SHA256_HEX_SIZE;
   const size_t to_read = hex_size * 2;  // CNonce + Response
 
   // Try to read remaining bytes (CNonce + Response)
@@ -710,55 +635,25 @@ bool ESPHomeOTAComponent::handle_auth_read_() {
   const char *cnonce = nonce + hex_size;
   const char *response = cnonce + hex_size;
 
-  // CRITICAL ESP32-S3: Hash objects must stay in same stack frame (no passing to other functions).
-  // Declare both hash objects in same stack frame, use pointer to select.
-  // NOTE: Both objects are declared here even though only one is used. This is REQUIRED for ESP32-S3
-  // hardware SHA acceleration - the object must exist in this stack frame for all operations.
-  // Do NOT try to "optimize" by creating the object inside the if block, as it would go out of scope.
-#ifdef USE_OTA_SHA256
-  sha256::SHA256 sha_hasher;
-#endif
-#ifdef USE_OTA_MD5
-  md5::MD5Digest md5_hasher;
-#endif
-  HashBase *hasher = nullptr;
+  // CRITICAL ESP32-S3 HARDWARE SHA ACCELERATION: Hash object must stay in same stack frame
+  // (no passing to other functions). All hash operations must happen in this function.
+  sha256::SHA256 hasher;
 
-#ifdef USE_OTA_SHA256
-  if (this->auth_type_ == ota::OTA_RESPONSE_REQUEST_SHA256_AUTH) {
-    hasher = &sha_hasher;
-  }
-#endif
-#ifdef USE_OTA_MD5
-  if (this->auth_type_ == ota::OTA_RESPONSE_REQUEST_AUTH) {
-    hasher = &md5_hasher;
-  }
-#endif
-
-  hasher->init();
-  hasher->add(this->password_.c_str(), this->password_.length());
-  hasher->add(nonce, hex_size * 2);  // Add both nonce and cnonce (contiguous in buffer)
-  hasher->calculate();
+  hasher.init();
+  hasher.add(this->password_.c_str(), this->password_.length());
+  hasher.add(nonce, hex_size * 2);  // Add both nonce and cnonce (contiguous in buffer)
+  hasher.calculate();
 
+  ESP_LOGV(TAG, "Auth: CNonce is %.*s", hex_size, cnonce);
 #if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
-  char log_buf[65];  // Fixed size for SHA256 hex (64) + null, works for MD5 (32) too
-  // Log CNonce
-  memcpy(log_buf, cnonce, hex_size);
-  log_buf[hex_size] = '\0';
-  ESP_LOGV(TAG, "Auth: CNonce is %s", log_buf);
-
-  // Log computed hash
-  hasher->get_hex(log_buf);
-  log_buf[hex_size] = '\0';
-  ESP_LOGV(TAG, "Auth: Result is %s", log_buf);
-
-  // Log received response
-  memcpy(log_buf, response, hex_size);
-  log_buf[hex_size] = '\0';
-  ESP_LOGV(TAG, "Auth: Response is %s", log_buf);
+  char computed_hash[SHA256_HEX_SIZE + 1];  // Buffer for hex-encoded hash (max expected length + null terminator)
+  hasher.get_hex(computed_hash);
+  ESP_LOGV(TAG, "Auth: Result is %.*s", hex_size, computed_hash);
 #endif
+  ESP_LOGV(TAG, "Auth: Response is %.*s", hex_size, response);
 
   // Compare response
-  bool matches = hasher->equals_hex(response);
+  bool matches = hasher.equals_hex(response);
 
   if (!matches) {
     this->log_auth_warning_(LOG_STR("Password mismatch"));
@@ -772,21 +667,6 @@ bool ESPHomeOTAComponent::handle_auth_read_() {
   return true;
 }
 
-size_t ESPHomeOTAComponent::get_auth_hex_size_() const {
-#ifdef USE_OTA_SHA256
-  if (this->auth_type_ == ota::OTA_RESPONSE_REQUEST_SHA256_AUTH) {
-    return SHA256_HEX_SIZE;
-  }
-#endif
-#ifdef USE_OTA_MD5
-  return MD5_HEX_SIZE;
-#else
-#ifndef USE_OTA_SHA256
-#error "Either USE_OTA_MD5 or USE_OTA_SHA256 must be defined when USE_OTA_PASSWORD is enabled"
-#endif
-#endif
-}
-
 void ESPHomeOTAComponent::cleanup_auth_() {
   this->auth_buf_ = nullptr;
   this->auth_buf_pos_ = 0;

esphome/components/esphome/ota/ota_esphome.h

@@ -44,10 +44,10 @@ class ESPHomeOTAComponent : public ota::OTAComponent {
   void handle_handshake_();
   void handle_data_();
 #ifdef USE_OTA_PASSWORD
+  static constexpr size_t SHA256_HEX_SIZE = 64;  // SHA256 hash as hex string (32 bytes * 2)
   bool handle_auth_send_();
   bool handle_auth_read_();
   bool select_auth_type_();
-  size_t get_auth_hex_size_() const;
   void cleanup_auth_();
   void log_auth_warning_(const LogString *msg);
 #endif  // USE_OTA_PASSWORD

esphome/components/espnow/espnow_component.cpp

@@ -6,6 +6,7 @@
 
 #include "esphome/core/application.h"
 #include "esphome/core/defines.h"
+#include "esphome/core/helpers.h"
 #include "esphome/core/log.h"
 
 #include <esp_event.h>
@@ -299,9 +300,10 @@ void ESPNowComponent::loop() {
         // Intentionally left as if instead of else in case the peer is added above
         if (esp_now_is_peer_exist(info.src_addr)) {
 #if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+          char hex_buf[format_hex_pretty_size(ESP_NOW_MAX_DATA_LEN)];
           ESP_LOGV(TAG, "<<< [%s -> %s] %s", format_mac_address_pretty(info.src_addr).c_str(),
                    format_mac_address_pretty(info.des_addr).c_str(),
-                   format_hex_pretty(packet->packet_.receive.data, packet->packet_.receive.size).c_str());
+                   format_hex_pretty_to(hex_buf, packet->packet_.receive.data, packet->packet_.receive.size));
 #endif
           if (memcmp(info.des_addr, ESPNOW_BROADCAST_ADDR, ESP_NOW_ETH_ALEN) == 0) {
             for (auto *handler : this->broadcasted_handlers_) {

esphome/components/ethernet/ethernet_component.cpp

@@ -1,5 +1,6 @@
 #include "ethernet_component.h"
 #include "esphome/core/application.h"
+#include "esphome/core/helpers.h"
 #include "esphome/core/log.h"
 #include "esphome/core/util.h"
 
@@ -39,6 +40,9 @@ namespace ethernet {
 
 static const char *const TAG = "ethernet";
 
+// PHY register size for hex logging
+static constexpr size_t PHY_REG_SIZE = 2;
+
 EthernetComponent *global_eth_component;  // NOLINT(cppcoreguidelines-avoid-non-const-global-variables)
 
 void EthernetComponent::log_error_and_mark_failed_(esp_err_t err, const char *message) {
@@ -644,6 +648,12 @@ void EthernetComponent::dump_connect_params_() {
     dns_ip2 = dns_getserver(1);
   }
 
+  // Use stack buffers for IP address formatting to avoid heap allocations
+  char ip_buf[network::IP_ADDRESS_BUFFER_SIZE];
+  char subnet_buf[network::IP_ADDRESS_BUFFER_SIZE];
+  char gateway_buf[network::IP_ADDRESS_BUFFER_SIZE];
+  char dns1_buf[network::IP_ADDRESS_BUFFER_SIZE];
+  char dns2_buf[network::IP_ADDRESS_BUFFER_SIZE];
   ESP_LOGCONFIG(TAG,
                 "  IP Address: %s\n"
                 "  Hostname: '%s'\n"
@@ -651,9 +661,9 @@ void EthernetComponent::dump_connect_params_() {
                 "  Gateway: %s\n"
                 "  DNS1: %s\n"
                 "  DNS2: %s",
-                network::IPAddress(&ip.ip).str().c_str(), App.get_name().c_str(),
-                network::IPAddress(&ip.netmask).str().c_str(), network::IPAddress(&ip.gw).str().c_str(),
-                network::IPAddress(dns_ip1).str().c_str(), network::IPAddress(dns_ip2).str().c_str());
+                network::IPAddress(&ip.ip).str_to(ip_buf), App.get_name().c_str(),
+                network::IPAddress(&ip.netmask).str_to(subnet_buf), network::IPAddress(&ip.gw).str_to(gateway_buf),
+                network::IPAddress(dns_ip1).str_to(dns1_buf), network::IPAddress(dns_ip2).str_to(dns2_buf));
 
 #if USE_NETWORK_IPV6
   struct esp_ip6_addr if_ip6s[CONFIG_LWIP_IPV6_NUM_ADDRESSES];
@@ -665,12 +675,13 @@ void EthernetComponent::dump_connect_params_() {
   }
 #endif /* USE_NETWORK_IPV6 */
 
+  char mac_buf[MAC_ADDRESS_PRETTY_BUFFER_SIZE];
   ESP_LOGCONFIG(TAG,
                 "  MAC Address: %s\n"
                 "  Is Full Duplex: %s\n"
                 "  Link Speed: %u",
-                this->get_eth_mac_address_pretty().c_str(), YESNO(this->get_duplex_mode() == ETH_DUPLEX_FULL),
-                this->get_link_speed() == ETH_SPEED_100M ? 100 : 10);
+                this->get_eth_mac_address_pretty_into_buffer(mac_buf),
+                YESNO(this->get_duplex_mode() == ETH_DUPLEX_FULL), this->get_link_speed() == ETH_SPEED_100M ? 100 : 10);
 }
 
 #ifdef USE_ETHERNET_SPI
@@ -711,11 +722,16 @@ void EthernetComponent::get_eth_mac_address_raw(uint8_t *mac) {
 }
 
 std::string EthernetComponent::get_eth_mac_address_pretty() {
+  char buf[MAC_ADDRESS_PRETTY_BUFFER_SIZE];
+  return std::string(this->get_eth_mac_address_pretty_into_buffer(buf));
+}
+
+const char *EthernetComponent::get_eth_mac_address_pretty_into_buffer(
+    std::span<char, MAC_ADDRESS_PRETTY_BUFFER_SIZE> buf) {
   uint8_t mac[6];
   get_eth_mac_address_raw(mac);
-  char buf[18];
-  format_mac_addr_upper(mac, buf);
-  return std::string(buf);
+  format_mac_addr_upper(mac, buf.data());
+  return buf.data();
 }
 
 eth_duplex_t EthernetComponent::get_duplex_mode() {
@@ -761,7 +777,10 @@ void EthernetComponent::ksz8081_set_clock_reference_(esp_eth_mac_t *mac) {
   uint32_t phy_control_2;
   err = mac->read_phy_reg(mac, this->phy_addr_, KSZ80XX_PC2R_REG_ADDR, &(phy_control_2));
   ESPHL_ERROR_CHECK(err, "Read PHY Control 2 failed");
-  ESP_LOGVV(TAG, "KSZ8081 PHY Control 2: %s", format_hex_pretty((u_int8_t *) &phy_control_2, 2).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERY_VERBOSE
+  char hex_buf[format_hex_pretty_size(PHY_REG_SIZE)];
+  ESP_LOGVV(TAG, "KSZ8081 PHY Control 2: %s", format_hex_pretty_to(hex_buf, (uint8_t *) &phy_control_2, PHY_REG_SIZE));
+#endif
 
   /*
    * Bit 7 is `RMII Reference Clock Select`. Default is `0`.
@@ -778,7 +797,10 @@ void EthernetComponent::ksz8081_set_clock_reference_(esp_eth_mac_t *mac) {
     ESPHL_ERROR_CHECK(err, "Write PHY Control 2 failed");
     err = mac->read_phy_reg(mac, this->phy_addr_, KSZ80XX_PC2R_REG_ADDR, &(phy_control_2));
     ESPHL_ERROR_CHECK(err, "Read PHY Control 2 failed");
-    ESP_LOGVV(TAG, "KSZ8081 PHY Control 2: %s", format_hex_pretty((u_int8_t *) &phy_control_2, 2).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERY_VERBOSE
+    ESP_LOGVV(TAG, "KSZ8081 PHY Control 2: %s",
+              format_hex_pretty_to(hex_buf, (uint8_t *) &phy_control_2, PHY_REG_SIZE));
+#endif
   }
 }
 #endif  // USE_ETHERNET_KSZ8081

esphome/components/ethernet/ethernet_component.h

@@ -3,6 +3,7 @@
 #include "esphome/core/component.h"
 #include "esphome/core/defines.h"
 #include "esphome/core/hal.h"
+#include "esphome/core/helpers.h"
 #include "esphome/components/network/ip_address.h"
 
 #ifdef USE_ESP32
@@ -93,6 +94,7 @@ class EthernetComponent : public Component {
   void set_use_address(const char *use_address);
   void get_eth_mac_address_raw(uint8_t *mac);
   std::string get_eth_mac_address_pretty();
+  const char *get_eth_mac_address_pretty_into_buffer(std::span<char, MAC_ADDRESS_PRETTY_BUFFER_SIZE> buf);
   eth_duplex_t get_duplex_mode();
   eth_speed_t get_link_speed();
   bool powerdown();

esphome/components/ethernet_info/ethernet_info_text_sensor.cpp

@@ -3,8 +3,7 @@
 
 #ifdef USE_ESP32
 
-namespace esphome {
-namespace ethernet_info {
+namespace esphome::ethernet_info {
 
 static const char *const TAG = "ethernet_info";
 
@@ -12,7 +11,6 @@ void IPAddressEthernetInfo::dump_config() { LOG_TEXT_SENSOR("", "EthernetInfo IP
 void DNSAddressEthernetInfo::dump_config() { LOG_TEXT_SENSOR("", "EthernetInfo DNS Address", this); }
 void MACAddressEthernetInfo::dump_config() { LOG_TEXT_SENSOR("", "EthernetInfo MAC Address", this); }
 
-}  // namespace ethernet_info
-}  // namespace esphome
+}  // namespace esphome::ethernet_info
 
 #endif  // USE_ESP32

esphome/components/ethernet_info/ethernet_info_text_sensor.h

@@ -6,8 +6,7 @@
 
 #ifdef USE_ESP32
 
-namespace esphome {
-namespace ethernet_info {
+namespace esphome::ethernet_info {
 
 class IPAddressEthernetInfo : public PollingComponent, public text_sensor::TextSensor {
  public:
@@ -40,21 +39,27 @@ class IPAddressEthernetInfo : public PollingComponent, public text_sensor::TextS
 class DNSAddressEthernetInfo : public PollingComponent, public text_sensor::TextSensor {
  public:
   void update() override {
-    auto dns_one = ethernet::global_eth_component->get_dns_address(0);
-    auto dns_two = ethernet::global_eth_component->get_dns_address(1);
+    auto dns1 = ethernet::global_eth_component->get_dns_address(0);
+    auto dns2 = ethernet::global_eth_component->get_dns_address(1);
 
-    std::string dns_results = dns_one.str() + " " + dns_two.str();
-
-    if (dns_results != this->last_results_) {
-      this->last_results_ = dns_results;
-      this->publish_state(dns_results);
+    if (dns1 != this->last_dns1_ || dns2 != this->last_dns2_) {
+      this->last_dns1_ = dns1;
+      this->last_dns2_ = dns2;
+      // IP_ADDRESS_BUFFER_SIZE (40) = max IP (39) + null; space reuses first null's slot
+      char buf[network::IP_ADDRESS_BUFFER_SIZE * 2];
+      dns1.str_to(buf);
+      size_t len1 = strlen(buf);
+      buf[len1] = ' ';
+      dns2.str_to(buf + len1 + 1);
+      this->publish_state(buf);
     }
   }
   float get_setup_priority() const override { return setup_priority::ETHERNET; }
   void dump_config() override;
 
  protected:
-  std::string last_results_;
+  network::IPAddress last_dns1_;
+  network::IPAddress last_dns2_;
 };
 
 class MACAddressEthernetInfo : public Component, public text_sensor::TextSensor {
@@ -64,7 +69,6 @@ class MACAddressEthernetInfo : public Component, public text_sensor::TextSensor
   void dump_config() override;
 };
 
-}  // namespace ethernet_info
-}  // namespace esphome
+}  // namespace esphome::ethernet_info
 
 #endif  // USE_ESP32

esphome/components/hlk_fm22x/hlk_fm22x.cpp

@@ -8,6 +8,9 @@ namespace esphome::hlk_fm22x {
 
 static const char *const TAG = "hlk_fm22x";
 
+// Maximum response size is 36 bytes (VERIFY reply: face_id + 32-byte name)
+static constexpr size_t HLK_FM22X_MAX_RESPONSE_SIZE = 36;
+
 void HlkFm22xComponent::setup() {
   ESP_LOGCONFIG(TAG, "Setting up HLK-FM22X...");
   this->set_enrolling_(false);
@@ -142,7 +145,10 @@ void HlkFm22xComponent::recv_command_() {
     data.push_back(byte);
   }
 
-  ESP_LOGV(TAG, "Recv type: 0x%.2X, data: %s", response_type, format_hex_pretty(data).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  char hex_buf[format_hex_pretty_size(HLK_FM22X_MAX_RESPONSE_SIZE)];
+  ESP_LOGV(TAG, "Recv type: 0x%.2X, data: %s", response_type, format_hex_pretty_to(hex_buf, data.data(), data.size()));
+#endif
 
   byte = this->read();
   if (byte != checksum) {

esphome/components/hlw8012/hlw8012.cpp

@@ -34,9 +34,9 @@ void HLW8012Component::setup() {
 }
 void HLW8012Component::dump_config() {
   ESP_LOGCONFIG(TAG, "HLW8012:");
-  LOG_PIN("  SEL Pin: ", this->sel_pin_)
-  LOG_PIN("  CF Pin: ", this->cf_pin_)
-  LOG_PIN("  CF1 Pin: ", this->cf1_pin_)
+  LOG_PIN("  SEL Pin: ", this->sel_pin_);
+  LOG_PIN("  CF Pin: ", this->cf_pin_);
+  LOG_PIN("  CF1 Pin: ", this->cf1_pin_);
   ESP_LOGCONFIG(TAG,
                 "  Change measurement mode every %" PRIu32 "\n"
                 "  Current resistor: %.1f mΩ\n"

esphome/components/hmac_md5/hmac_md5.h

@@ -30,7 +30,7 @@ class HmacMD5 {
   void get_bytes(uint8_t *output);
 
   /// Retrieve the HMAC-MD5 digest as hex characters.
-  /// The output must be able to hold 32 bytes or more.
+  /// The output must be able to hold 33 bytes or more (32 hex chars + null terminator).
   void get_hex(char *output);
 
   /// Compare the digest against a provided byte-encoded digest (16 bytes).

esphome/components/hmac_sha256/hmac_sha256.h

@@ -35,7 +35,7 @@ class HmacSHA256 {
   void get_bytes(uint8_t *output);
 
   /// Retrieve the HMAC-SHA256 digest as hex characters.
-  /// The output must be able to hold 64 bytes or more.
+  /// The output must be able to hold 65 bytes or more (64 hex chars + null terminator).
   void get_hex(char *output);
 
   /// Compare the digest against a provided byte-encoded digest (32 bytes).

esphome/components/homeassistant/binary_sensor/homeassistant_binary_sensor.cpp

@@ -1,6 +1,7 @@
 #include "homeassistant_binary_sensor.h"
-#include "esphome/core/log.h"
 #include "esphome/components/api/api_server.h"
+#include "esphome/core/log.h"
+#include "esphome/core/string_ref.h"
 
 namespace esphome {
 namespace homeassistant {
@@ -8,31 +9,30 @@ namespace homeassistant {
 static const char *const TAG = "homeassistant.binary_sensor";
 
 void HomeassistantBinarySensor::setup() {
-  api::global_api_server->subscribe_home_assistant_state(
-      this->entity_id_, this->attribute_, [this](const std::string &state) {
-        auto val = parse_on_off(state.c_str());
-        switch (val) {
-          case PARSE_NONE:
-          case PARSE_TOGGLE:
-            ESP_LOGW(TAG, "Can't convert '%s' to binary state!", state.c_str());
-            break;
-          case PARSE_ON:
-          case PARSE_OFF:
-            bool new_state = val == PARSE_ON;
-            if (this->attribute_ != nullptr) {
-              ESP_LOGD(TAG, "'%s::%s': Got attribute state %s", this->entity_id_, this->attribute_, ONOFF(new_state));
-            } else {
-              ESP_LOGD(TAG, "'%s': Got state %s", this->entity_id_, ONOFF(new_state));
-            }
-            if (this->initial_) {
-              this->publish_initial_state(new_state);
-            } else {
-              this->publish_state(new_state);
-            }
-            break;
+  api::global_api_server->subscribe_home_assistant_state(this->entity_id_, this->attribute_, [this](StringRef state) {
+    auto val = parse_on_off(state.c_str());
+    switch (val) {
+      case PARSE_NONE:
+      case PARSE_TOGGLE:
+        ESP_LOGW(TAG, "Can't convert '%s' to binary state!", state.c_str());
+        break;
+      case PARSE_ON:
+      case PARSE_OFF:
+        bool new_state = val == PARSE_ON;
+        if (this->attribute_ != nullptr) {
+          ESP_LOGD(TAG, "'%s::%s': Got attribute state %s", this->entity_id_, this->attribute_, ONOFF(new_state));
+        } else {
+          ESP_LOGD(TAG, "'%s': Got state %s", this->entity_id_, ONOFF(new_state));
         }
-        this->initial_ = false;
-      });
+        if (this->initial_) {
+          this->publish_initial_state(new_state);
+        } else {
+          this->publish_state(new_state);
+        }
+        break;
+    }
+    this->initial_ = false;
+  });
 }
 void HomeassistantBinarySensor::dump_config() {
   LOG_BINARY_SENSOR("", "Homeassistant Binary Sensor", this);

esphome/components/homeassistant/number/homeassistant_number.cpp

@@ -3,14 +3,15 @@
 #include "esphome/components/api/api_pb2.h"
 #include "esphome/components/api/api_server.h"
 #include "esphome/core/log.h"
+#include "esphome/core/string_ref.h"
 
 namespace esphome {
 namespace homeassistant {
 
 static const char *const TAG = "homeassistant.number";
 
-void HomeassistantNumber::state_changed_(const std::string &state) {
-  auto number_value = parse_number<float>(state);
+void HomeassistantNumber::state_changed_(StringRef state) {
+  auto number_value = parse_number<float>(state.c_str());
   if (!number_value.has_value()) {
     ESP_LOGW(TAG, "'%s': Can't convert '%s' to number!", this->entity_id_, state.c_str());
     this->publish_state(NAN);
@@ -23,8 +24,8 @@ void HomeassistantNumber::state_changed_(const std::string &state) {
   this->publish_state(number_value.value());
 }
 
-void HomeassistantNumber::min_retrieved_(const std::string &min) {
-  auto min_value = parse_number<float>(min);
+void HomeassistantNumber::min_retrieved_(StringRef min) {
+  auto min_value = parse_number<float>(min.c_str());
   if (!min_value.has_value()) {
     ESP_LOGE(TAG, "'%s': Can't convert 'min' value '%s' to number!", this->entity_id_, min.c_str());
     return;
@@ -33,8 +34,8 @@ void HomeassistantNumber::min_retrieved_(const std::string &min) {
   this->traits.set_min_value(min_value.value());
 }
 
-void HomeassistantNumber::max_retrieved_(const std::string &max) {
-  auto max_value = parse_number<float>(max);
+void HomeassistantNumber::max_retrieved_(StringRef max) {
+  auto max_value = parse_number<float>(max.c_str());
   if (!max_value.has_value()) {
     ESP_LOGE(TAG, "'%s': Can't convert 'max' value '%s' to number!", this->entity_id_, max.c_str());
     return;
@@ -43,8 +44,8 @@ void HomeassistantNumber::max_retrieved_(const std::string &max) {
   this->traits.set_max_value(max_value.value());
 }
 
-void HomeassistantNumber::step_retrieved_(const std::string &step) {
-  auto step_value = parse_number<float>(step);
+void HomeassistantNumber::step_retrieved_(StringRef step) {
+  auto step_value = parse_number<float>(step.c_str());
   if (!step_value.has_value()) {
     ESP_LOGE(TAG, "'%s': Can't convert 'step' value '%s' to number!", this->entity_id_, step.c_str());
     return;

esphome/components/homeassistant/number/homeassistant_number.h

@@ -1,10 +1,8 @@
 #pragma once
 
-#include <map>
-#include <string>
-
 #include "esphome/components/number/number.h"
 #include "esphome/core/component.h"
+#include "esphome/core/string_ref.h"
 
 namespace esphome {
 namespace homeassistant {
@@ -18,10 +16,10 @@ class HomeassistantNumber : public number::Number, public Component {
   float get_setup_priority() const override;
 
  protected:
-  void state_changed_(const std::string &state);
-  void min_retrieved_(const std::string &min);
-  void max_retrieved_(const std::string &max);
-  void step_retrieved_(const std::string &step);
+  void state_changed_(StringRef state);
+  void min_retrieved_(StringRef min);
+  void max_retrieved_(StringRef max);
+  void step_retrieved_(StringRef step);
 
   void control(float value) override;
 

esphome/components/homeassistant/sensor/homeassistant_sensor.cpp

@@ -1,6 +1,7 @@
 #include "homeassistant_sensor.h"
-#include "esphome/core/log.h"
 #include "esphome/components/api/api_server.h"
+#include "esphome/core/log.h"
+#include "esphome/core/string_ref.h"
 
 namespace esphome {
 namespace homeassistant {
@@ -8,22 +9,21 @@ namespace homeassistant {
 static const char *const TAG = "homeassistant.sensor";
 
 void HomeassistantSensor::setup() {
-  api::global_api_server->subscribe_home_assistant_state(
-      this->entity_id_, this->attribute_, [this](const std::string &state) {
-        auto val = parse_number<float>(state);
-        if (!val.has_value()) {
-          ESP_LOGW(TAG, "'%s': Can't convert '%s' to number!", this->entity_id_, state.c_str());
-          this->publish_state(NAN);
-          return;
-        }
+  api::global_api_server->subscribe_home_assistant_state(this->entity_id_, this->attribute_, [this](StringRef state) {
+    auto val = parse_number<float>(state.c_str());
+    if (!val.has_value()) {
+      ESP_LOGW(TAG, "'%s': Can't convert '%s' to number!", this->entity_id_, state.c_str());
+      this->publish_state(NAN);
+      return;
+    }
 
-        if (this->attribute_ != nullptr) {
-          ESP_LOGD(TAG, "'%s::%s': Got attribute state %.2f", this->entity_id_, this->attribute_, *val);
-        } else {
-          ESP_LOGD(TAG, "'%s': Got state %.2f", this->entity_id_, *val);
-        }
-        this->publish_state(*val);
-      });
+    if (this->attribute_ != nullptr) {
+      ESP_LOGD(TAG, "'%s::%s': Got attribute state %.2f", this->entity_id_, this->attribute_, *val);
+    } else {
+      ESP_LOGD(TAG, "'%s': Got state %.2f", this->entity_id_, *val);
+    }
+    this->publish_state(*val);
+  });
 }
 void HomeassistantSensor::dump_config() {
   LOG_SENSOR("", "Homeassistant Sensor", this);

esphome/components/homeassistant/switch/homeassistant_switch.cpp

@@ -1,6 +1,7 @@
 #include "homeassistant_switch.h"
 #include "esphome/components/api/api_server.h"
 #include "esphome/core/log.h"
+#include "esphome/core/string_ref.h"
 
 namespace esphome {
 namespace homeassistant {
@@ -10,7 +11,7 @@ static const char *const TAG = "homeassistant.switch";
 using namespace esphome::switch_;
 
 void HomeassistantSwitch::setup() {
-  api::global_api_server->subscribe_home_assistant_state(this->entity_id_, nullptr, [this](const std::string &state) {
+  api::global_api_server->subscribe_home_assistant_state(this->entity_id_, nullptr, [this](StringRef state) {
     auto val = parse_on_off(state.c_str());
     switch (val) {
       case PARSE_NONE:

esphome/components/homeassistant/text_sensor/homeassistant_text_sensor.cpp

@@ -1,6 +1,7 @@
 #include "homeassistant_text_sensor.h"
-#include "esphome/core/log.h"
 #include "esphome/components/api/api_server.h"
+#include "esphome/core/log.h"
+#include "esphome/core/string_ref.h"
 
 namespace esphome {
 namespace homeassistant {
@@ -8,15 +9,14 @@ namespace homeassistant {
 static const char *const TAG = "homeassistant.text_sensor";
 
 void HomeassistantTextSensor::setup() {
-  api::global_api_server->subscribe_home_assistant_state(
-      this->entity_id_, this->attribute_, [this](const std::string &state) {
-        if (this->attribute_ != nullptr) {
-          ESP_LOGD(TAG, "'%s::%s': Got attribute state '%s'", this->entity_id_, this->attribute_, state.c_str());
-        } else {
-          ESP_LOGD(TAG, "'%s': Got state '%s'", this->entity_id_, state.c_str());
-        }
-        this->publish_state(state);
-      });
+  api::global_api_server->subscribe_home_assistant_state(this->entity_id_, this->attribute_, [this](StringRef state) {
+    if (this->attribute_ != nullptr) {
+      ESP_LOGD(TAG, "'%s::%s': Got attribute state '%s'", this->entity_id_, this->attribute_, state.c_str());
+    } else {
+      ESP_LOGD(TAG, "'%s': Got state '%s'", this->entity_id_, state.c_str());
+    }
+    this->publish_state(state.str());
+  });
 }
 void HomeassistantTextSensor::dump_config() {
   LOG_TEXT_SENSOR("", "Homeassistant Text Sensor", this);

esphome/components/host/gpio.cpp

@@ -25,11 +25,7 @@ void HostGPIOPin::attach_interrupt(void (*func)(void *), void *arg, gpio::Interr
 }
 void HostGPIOPin::pin_mode(gpio::Flags flags) { ESP_LOGD(TAG, "Setting pin %d mode to %02X", pin_, (uint32_t) flags); }
 
-std::string HostGPIOPin::dump_summary() const {
-  char buffer[32];
-  snprintf(buffer, sizeof(buffer), "GPIO%u", pin_);
-  return buffer;
-}
+size_t HostGPIOPin::dump_summary(char *buffer, size_t len) const { return snprintf(buffer, len, "GPIO%u", this->pin_); }
 
 bool HostGPIOPin::digital_read() { return inverted_; }
 void HostGPIOPin::digital_write(bool value) {

esphome/components/host/gpio.h

@@ -17,7 +17,7 @@ class HostGPIOPin : public InternalGPIOPin {
   void pin_mode(gpio::Flags flags) override;
   bool digital_read() override;
   void digital_write(bool value) override;
-  std::string dump_summary() const override;
+  size_t dump_summary(char *buffer, size_t len) const override;
   void detach_interrupt() const override;
   ISRInternalGPIOPin to_isr() const override;
   uint8_t get_pin() const override { return pin_; }

esphome/components/hte501/hte501.cpp

@@ -7,6 +7,8 @@ namespace hte501 {
 
 static const char *const TAG = "hte501";
 
+static constexpr size_t HTE501_SERIAL_NUMBER_SIZE = 7;
+
 void HTE501Component::setup() {
   uint8_t address[] = {0x70, 0x29};
   uint8_t identification[9];
@@ -16,7 +18,10 @@ void HTE501Component::setup() {
     this->mark_failed();
     return;
   }
-  ESP_LOGV(TAG, "    Serial Number: 0x%s", format_hex(identification + 0, 7).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  char serial_hex[format_hex_size(HTE501_SERIAL_NUMBER_SIZE)];
+#endif
+  ESP_LOGV(TAG, "    Serial Number: 0x%s", format_hex_to(serial_hex, identification, HTE501_SERIAL_NUMBER_SIZE));
 }
 
 void HTE501Component::dump_config() {

esphome/components/http_request/ota/ota_http_request.cpp

@@ -7,7 +7,7 @@
 #include "esphome/components/md5/md5.h"
 #include "esphome/components/watchdog/watchdog.h"
 #include "esphome/components/ota/ota_backend.h"
-#include "esphome/components/ota/ota_backend_arduino_esp8266.h"
+#include "esphome/components/ota/ota_backend_esp8266.h"
 #include "esphome/components/ota/ota_backend_arduino_rp2040.h"
 #include "esphome/components/ota/ota_backend_esp_idf.h"
 

esphome/components/hub75/hub75.cpp

@@ -111,6 +111,9 @@ void HOT HUB75Display::draw_pixel_at(int x, int y, Color color) {
   if (x >= this->get_width_internal() || x < 0 || y >= this->get_height_internal() || y < 0) [[unlikely]]
     return;
 
+  if (!this->get_clipping().inside(x, y))
+    return;
+
   driver_->set_pixel(x, y, color.r, color.g, color.b);
   App.feed_wdt();
 }

esphome/components/i2c/i2c_bus_arduino.cpp

@@ -12,6 +12,9 @@ namespace i2c {
 
 static const char *const TAG = "i2c.arduino";
 
+// Maximum bytes to log in hex format (truncates larger transfers)
+static constexpr size_t I2C_MAX_LOG_BYTES = 32;
+
 void ArduinoI2CBus::setup() {
   recover_();
 
@@ -107,7 +110,10 @@ ErrorCode ArduinoI2CBus::write_readv(uint8_t address, const uint8_t *write_buffe
     return ERROR_NOT_INITIALIZED;
   }
 
-  ESP_LOGV(TAG, "0x%02X TX %s", address, format_hex_pretty(write_buffer, write_count).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  char hex_buf[format_hex_pretty_size(I2C_MAX_LOG_BYTES)];
+  ESP_LOGV(TAG, "0x%02X TX %s", address, format_hex_pretty_to(hex_buf, write_buffer, write_count));
+#endif
 
   uint8_t status = 0;
   if (write_count != 0 || read_count == 0) {

esphome/components/i2c/i2c_bus_esp_idf.cpp

@@ -15,6 +15,9 @@ namespace i2c {
 
 static const char *const TAG = "i2c.idf";
 
+// Maximum bytes to log in hex format (truncates larger transfers)
+static constexpr size_t I2C_MAX_LOG_BYTES = 32;
+
 void IDFI2CBus::setup() {
   static i2c_port_t next_hp_port = I2C_NUM_0;
 #if SOC_LP_I2C_SUPPORTED
@@ -147,7 +150,10 @@ ErrorCode IDFI2CBus::write_readv(uint8_t address, const uint8_t *write_buffer, s
     jobs[num_jobs++].write.total_bytes = 1;
   } else {
     if (write_count != 0) {
-      ESP_LOGV(TAG, "0x%02X TX %s", address, format_hex_pretty(write_buffer, write_count).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+      char hex_buf[format_hex_pretty_size(I2C_MAX_LOG_BYTES)];
+      ESP_LOGV(TAG, "0x%02X TX %s", address, format_hex_pretty_to(hex_buf, write_buffer, write_count));
+#endif
       jobs[num_jobs++].command = I2C_MASTER_CMD_START;
       jobs[num_jobs].command = I2C_MASTER_CMD_WRITE;
       jobs[num_jobs].write.ack_check = true;

esphome/components/internal_temperature/internal_temperature.cpp

@@ -8,8 +8,9 @@ extern "C" {
 uint8_t temprature_sens_read();
 }
 #elif defined(USE_ESP32_VARIANT_ESP32C2) || defined(USE_ESP32_VARIANT_ESP32C3) || \
-    defined(USE_ESP32_VARIANT_ESP32C6) || defined(USE_ESP32_VARIANT_ESP32C61) || defined(USE_ESP32_VARIANT_ESP32H2) || \
-    defined(USE_ESP32_VARIANT_ESP32P4) || defined(USE_ESP32_VARIANT_ESP32S2) || defined(USE_ESP32_VARIANT_ESP32S3)
+    defined(USE_ESP32_VARIANT_ESP32C5) || defined(USE_ESP32_VARIANT_ESP32C6) || defined(USE_ESP32_VARIANT_ESP32C61) || \
+    defined(USE_ESP32_VARIANT_ESP32H2) || defined(USE_ESP32_VARIANT_ESP32P4) || defined(USE_ESP32_VARIANT_ESP32S2) || \
+    defined(USE_ESP32_VARIANT_ESP32S3)
 #include "driver/temperature_sensor.h"
 #endif  // USE_ESP32_VARIANT
 #endif  // USE_ESP32
@@ -27,9 +28,9 @@ namespace internal_temperature {
 
 static const char *const TAG = "internal_temperature";
 #ifdef USE_ESP32
-#if defined(USE_ESP32_VARIANT_ESP32C2) || defined(USE_ESP32_VARIANT_ESP32C3) || defined(USE_ESP32_VARIANT_ESP32C6) || \
-    defined(USE_ESP32_VARIANT_ESP32C61) || defined(USE_ESP32_VARIANT_ESP32H2) || defined(USE_ESP32_VARIANT_ESP32P4) || \
-    defined(USE_ESP32_VARIANT_ESP32S2) || defined(USE_ESP32_VARIANT_ESP32S3)
+#if defined(USE_ESP32_VARIANT_ESP32C2) || defined(USE_ESP32_VARIANT_ESP32C3) || defined(USE_ESP32_VARIANT_ESP32C5) || \
+    defined(USE_ESP32_VARIANT_ESP32C6) || defined(USE_ESP32_VARIANT_ESP32C61) || defined(USE_ESP32_VARIANT_ESP32H2) || \
+    defined(USE_ESP32_VARIANT_ESP32P4) || defined(USE_ESP32_VARIANT_ESP32S2) || defined(USE_ESP32_VARIANT_ESP32S3)
 static temperature_sensor_handle_t tsensNew = NULL;
 #endif  // USE_ESP32_VARIANT
 #endif  // USE_ESP32
@@ -44,8 +45,9 @@ void InternalTemperatureSensor::update() {
   temperature = (raw - 32) / 1.8f;
   success = (raw != 128);
 #elif defined(USE_ESP32_VARIANT_ESP32C2) || defined(USE_ESP32_VARIANT_ESP32C3) || \
-    defined(USE_ESP32_VARIANT_ESP32C6) || defined(USE_ESP32_VARIANT_ESP32C61) || defined(USE_ESP32_VARIANT_ESP32H2) || \
-    defined(USE_ESP32_VARIANT_ESP32P4) || defined(USE_ESP32_VARIANT_ESP32S2) || defined(USE_ESP32_VARIANT_ESP32S3)
+    defined(USE_ESP32_VARIANT_ESP32C5) || defined(USE_ESP32_VARIANT_ESP32C6) || defined(USE_ESP32_VARIANT_ESP32C61) || \
+    defined(USE_ESP32_VARIANT_ESP32H2) || defined(USE_ESP32_VARIANT_ESP32P4) || defined(USE_ESP32_VARIANT_ESP32S2) || \
+    defined(USE_ESP32_VARIANT_ESP32S3)
   esp_err_t result = temperature_sensor_get_celsius(tsensNew, &temperature);
   success = (result == ESP_OK);
   if (!success) {
@@ -81,9 +83,9 @@ void InternalTemperatureSensor::update() {
 
 void InternalTemperatureSensor::setup() {
 #ifdef USE_ESP32
-#if defined(USE_ESP32_VARIANT_ESP32C2) || defined(USE_ESP32_VARIANT_ESP32C3) || defined(USE_ESP32_VARIANT_ESP32C6) || \
-    defined(USE_ESP32_VARIANT_ESP32C61) || defined(USE_ESP32_VARIANT_ESP32H2) || defined(USE_ESP32_VARIANT_ESP32P4) || \
-    defined(USE_ESP32_VARIANT_ESP32S2) || defined(USE_ESP32_VARIANT_ESP32S3)
+#if defined(USE_ESP32_VARIANT_ESP32C2) || defined(USE_ESP32_VARIANT_ESP32C3) || defined(USE_ESP32_VARIANT_ESP32C5) || \
+    defined(USE_ESP32_VARIANT_ESP32C6) || defined(USE_ESP32_VARIANT_ESP32C61) || defined(USE_ESP32_VARIANT_ESP32H2) || \
+    defined(USE_ESP32_VARIANT_ESP32P4) || defined(USE_ESP32_VARIANT_ESP32S2) || defined(USE_ESP32_VARIANT_ESP32S3)
   temperature_sensor_config_t tsens_config = TEMPERATURE_SENSOR_CONFIG_DEFAULT(-10, 80);
 
   esp_err_t result = temperature_sensor_install(&tsens_config, &tsensNew);

esphome/components/jsn_sr04t/jsn_sr04t.cpp

@@ -39,7 +39,9 @@ void Jsnsr04tComponent::check_buffer_() {
       ESP_LOGV(TAG, "Distance from sensor: %umm, %.3fm", distance, meters);
       this->publish_state(meters);
     } else {
-      ESP_LOGW(TAG, "Invalid data read from sensor: %s", format_hex_pretty(this->buffer_).c_str());
+      char hex_buf[format_hex_pretty_size(4)];
+      ESP_LOGW(TAG, "Invalid data read from sensor: %s",
+               format_hex_pretty_to(hex_buf, this->buffer_.data(), this->buffer_.size()));
     }
   } else {
     ESP_LOGW(TAG, "checksum failed: %02x != %02x", checksum, this->buffer_[3]);

esphome/components/kuntze/kuntze.cpp

@@ -1,4 +1,5 @@
 #include "kuntze.h"
+#include "esphome/core/helpers.h"
 #include "esphome/core/log.h"
 #include "esphome/core/application.h"
 
@@ -10,11 +11,17 @@ static const char *const TAG = "kuntze";
 static const uint8_t CMD_READ_REG = 0x03;
 static const uint16_t REGISTER[] = {4136, 4160, 4680, 6000, 4688, 4728, 5832};
 
+// Maximum bytes to log for Modbus responses (2 registers = 4 bytes, plus byte count = 5 bytes)
+static constexpr size_t KUNTZE_MAX_LOG_BYTES = 8;
+
 void Kuntze::on_modbus_data(const std::vector<uint8_t> &data) {
   auto get_16bit = [&](int i) -> uint16_t { return (uint16_t(data[i * 2]) << 8) | uint16_t(data[i * 2 + 1]); };
 
   this->waiting_ = false;
-  ESP_LOGV(TAG, "Data: %s", format_hex_pretty(data).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+  char hex_buf[format_hex_pretty_size(KUNTZE_MAX_LOG_BYTES)];
+#endif
+  ESP_LOGV(TAG, "Data: %s", format_hex_pretty_to(hex_buf, data.data(), data.size()));
 
   float value = (float) get_16bit(0);
   for (int i = 0; i < data[3]; i++)

esphome/components/ld2410/ld2410.cpp

@@ -413,7 +413,8 @@ bool LD2410Component::handle_ack_data_() {
     return true;
   }
   if (!ld2410::validate_header_footer(CMD_FRAME_HEADER, this->buffer_data_)) {
-    ESP_LOGW(TAG, "Invalid header: %s", format_hex_pretty(this->buffer_data_, HEADER_FOOTER_SIZE).c_str());
+    char hex_buf[format_hex_pretty_size(HEADER_FOOTER_SIZE)];
+    ESP_LOGW(TAG, "Invalid header: %s", format_hex_pretty_to(hex_buf, this->buffer_data_, HEADER_FOOTER_SIZE));
     return true;
   }
   if (this->buffer_data_[COMMAND_STATUS] != 0x01) {
@@ -597,11 +598,17 @@ void LD2410Component::readline_(int readch) {
     return;  // Not enough data to process yet
   }
   if (ld2410::validate_header_footer(DATA_FRAME_FOOTER, &this->buffer_data_[this->buffer_pos_ - 4])) {
-    ESP_LOGV(TAG, "Handling Periodic Data: %s", format_hex_pretty(this->buffer_data_, this->buffer_pos_).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+    char hex_buf[format_hex_pretty_size(MAX_LINE_LENGTH)];
+    ESP_LOGV(TAG, "Handling Periodic Data: %s", format_hex_pretty_to(hex_buf, this->buffer_data_, this->buffer_pos_));
+#endif
     this->handle_periodic_data_();
     this->buffer_pos_ = 0;  // Reset position index for next message
   } else if (ld2410::validate_header_footer(CMD_FRAME_FOOTER, &this->buffer_data_[this->buffer_pos_ - 4])) {
-    ESP_LOGV(TAG, "Handling Ack Data: %s", format_hex_pretty(this->buffer_data_, this->buffer_pos_).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+    char hex_buf[format_hex_pretty_size(MAX_LINE_LENGTH)];
+    ESP_LOGV(TAG, "Handling Ack Data: %s", format_hex_pretty_to(hex_buf, this->buffer_data_, this->buffer_pos_));
+#endif
     if (this->handle_ack_data_()) {
       this->buffer_pos_ = 0;  // Reset position index for next message
     } else {

esphome/components/ld2412/ld2412.cpp

@@ -457,7 +457,8 @@ bool LD2412Component::handle_ack_data_() {
     return true;
   }
   if (!ld2412::validate_header_footer(CMD_FRAME_HEADER, this->buffer_data_)) {
-    ESP_LOGW(TAG, "Invalid header: %s", format_hex_pretty(this->buffer_data_, HEADER_FOOTER_SIZE).c_str());
+    char hex_buf[format_hex_pretty_size(HEADER_FOOTER_SIZE)];
+    ESP_LOGW(TAG, "Invalid header: %s", format_hex_pretty_to(hex_buf, this->buffer_data_, HEADER_FOOTER_SIZE));
     return true;
   }
   if (this->buffer_data_[COMMAND_STATUS] != 0x01) {
@@ -670,11 +671,17 @@ void LD2412Component::readline_(int readch) {
     return;  // Not enough data to process yet
   }
   if (ld2412::validate_header_footer(DATA_FRAME_FOOTER, &this->buffer_data_[this->buffer_pos_ - 4])) {
-    ESP_LOGV(TAG, "Handling Periodic Data: %s", format_hex_pretty(this->buffer_data_, this->buffer_pos_).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+    char hex_buf[format_hex_pretty_size(MAX_LINE_LENGTH)];
+    ESP_LOGV(TAG, "Handling Periodic Data: %s", format_hex_pretty_to(hex_buf, this->buffer_data_, this->buffer_pos_));
+#endif
     this->handle_periodic_data_();
     this->buffer_pos_ = 0;  // Reset position index for next message
   } else if (ld2412::validate_header_footer(CMD_FRAME_FOOTER, &this->buffer_data_[this->buffer_pos_ - 4])) {
-    ESP_LOGV(TAG, "Handling Ack Data: %s", format_hex_pretty(this->buffer_data_, this->buffer_pos_).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+    char hex_buf[format_hex_pretty_size(MAX_LINE_LENGTH)];
+    ESP_LOGV(TAG, "Handling Ack Data: %s", format_hex_pretty_to(hex_buf, this->buffer_data_, this->buffer_pos_));
+#endif
     if (this->handle_ack_data_()) {
       this->buffer_pos_ = 0;  // Reset position index for next message
     } else {

esphome/components/ld2450/ld2450.cpp

@@ -607,7 +607,8 @@ bool LD2450Component::handle_ack_data_() {
     return true;
   }
   if (!ld2450::validate_header_footer(CMD_FRAME_HEADER, this->buffer_data_)) {
-    ESP_LOGW(TAG, "Invalid header: %s", format_hex_pretty(this->buffer_data_, HEADER_FOOTER_SIZE).c_str());
+    char hex_buf[format_hex_pretty_size(HEADER_FOOTER_SIZE)];
+    ESP_LOGW(TAG, "Invalid header: %s", format_hex_pretty_to(hex_buf, this->buffer_data_, HEADER_FOOTER_SIZE));
     return true;
   }
   if (this->buffer_data_[COMMAND_STATUS] != 0x01) {
@@ -758,11 +759,17 @@ void LD2450Component::readline_(int readch) {
   }
   if (this->buffer_data_[this->buffer_pos_ - 2] == DATA_FRAME_FOOTER[0] &&
       this->buffer_data_[this->buffer_pos_ - 1] == DATA_FRAME_FOOTER[1]) {
-    ESP_LOGV(TAG, "Handling Periodic Data: %s", format_hex_pretty(this->buffer_data_, this->buffer_pos_).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+    char hex_buf[format_hex_pretty_size(MAX_LINE_LENGTH)];
+    ESP_LOGV(TAG, "Handling Periodic Data: %s", format_hex_pretty_to(hex_buf, this->buffer_data_, this->buffer_pos_));
+#endif
     this->handle_periodic_data_();
     this->buffer_pos_ = 0;  // Reset position index for next frame
   } else if (ld2450::validate_header_footer(CMD_FRAME_FOOTER, &this->buffer_data_[this->buffer_pos_ - 4])) {
-    ESP_LOGV(TAG, "Handling Ack Data: %s", format_hex_pretty(this->buffer_data_, this->buffer_pos_).c_str());
+#if ESPHOME_LOG_LEVEL >= ESPHOME_LOG_LEVEL_VERBOSE
+    char hex_buf[format_hex_pretty_size(MAX_LINE_LENGTH)];
+    ESP_LOGV(TAG, "Handling Ack Data: %s", format_hex_pretty_to(hex_buf, this->buffer_data_, this->buffer_pos_));
+#endif
     if (this->handle_ack_data_()) {
       this->buffer_pos_ = 0;  // Reset position index for next message
     } else {

esphome/components/libretiny/gpio_arduino.cpp

@@ -63,10 +63,8 @@ void ArduinoInternalGPIOPin::pin_mode(gpio::Flags flags) {
   pinMode(pin_, flags_to_mode(flags));  // NOLINT
 }
 
-std::string ArduinoInternalGPIOPin::dump_summary() const {
-  char buffer[32];
-  snprintf(buffer, sizeof(buffer), "%u", pin_);
-  return buffer;
+size_t ArduinoInternalGPIOPin::dump_summary(char *buffer, size_t len) const {
+  return snprintf(buffer, len, "%u", this->pin_);
 }
 
 bool ArduinoInternalGPIOPin::digital_read() {

esphome/components/libretiny/gpio_arduino.h

@@ -16,7 +16,7 @@ class ArduinoInternalGPIOPin : public InternalGPIOPin {
   void pin_mode(gpio::Flags flags) override;
   bool digital_read() override;
   void digital_write(bool value) override;
-  std::string dump_summary() const override;
+  size_t dump_summary(char *buffer, size_t len) const override;
   void detach_interrupt() const override;
   ISRInternalGPIOPin to_isr() const override;
   uint8_t get_pin() const override { return pin_; }

esphome/components/light/light_json_schema.cpp

@@ -36,7 +36,7 @@ static const char *get_color_mode_json_str(ColorMode mode) {
 void LightJSONSchema::dump_json(LightState &state, JsonObject root) {
   // NOLINTNEXTLINE(clang-analyzer-cplusplus.NewDeleteLeaks) false positive with ArduinoJson
   if (state.supports_effects()) {
-    root[ESPHOME_F("effect")] = state.get_effect_name();
+    root[ESPHOME_F("effect")] = state.get_effect_name_ref();
     root[ESPHOME_F("effect_index")] = state.get_current_effect_index();
     root[ESPHOME_F("effect_count")] = state.get_effect_count();
   }

esphome/components/logger/__init__.py

@@ -337,6 +337,22 @@ async def to_code(config):
     is_at_least_very_verbose = this_severity >= very_verbose_severity
     has_serial_logging = baud_rate != 0
 
+    # Add defines for which Serial object is needed (allows linker to exclude unused)
+    if CORE.is_esp8266:
+        hw_uart = config.get(CONF_HARDWARE_UART, UART0)
+        if has_serial_logging and hw_uart in (UART0, UART0_SWAP):
+            cg.add_define("USE_ESP8266_LOGGER_SERIAL")
+            # Exclude Serial1 from Arduino build
+            cg.add_build_flag("-DNO_GLOBAL_SERIAL1")
+        elif has_serial_logging and hw_uart == UART1:
+            cg.add_define("USE_ESP8266_LOGGER_SERIAL1")
+            # Exclude Serial from Arduino build
+            cg.add_build_flag("-DNO_GLOBAL_SERIAL")
+        else:
+            # No serial logging - exclude both
+            cg.add_build_flag("-DNO_GLOBAL_SERIAL")
+            cg.add_build_flag("-DNO_GLOBAL_SERIAL1")
+
     if (
         (CORE.is_esp8266 or CORE.is_rp2040)
         and has_serial_logging

esphome/components/logger/logger.cpp

@@ -65,8 +65,8 @@ void HOT Logger::log_vprintf_(uint8_t level, const char *tag, int line, const ch
     uint16_t buffer_at = 0;                         // Initialize buffer position
     this->format_log_to_buffer_with_terminator_(level, tag, line, format, args, console_buffer, &buffer_at,
                                                 MAX_CONSOLE_LOG_MSG_SIZE);
-    // Add newline if platform needs it (ESP32 doesn't add via write_msg_)
-    this->add_newline_to_buffer_if_needed_(console_buffer, &buffer_at, MAX_CONSOLE_LOG_MSG_SIZE);
+    // Add newline before writing to console
+    this->add_newline_to_buffer_(console_buffer, &buffer_at, MAX_CONSOLE_LOG_MSG_SIZE);
     this->write_msg_(console_buffer, buffer_at);
   }